diff --git a/MFaaP.MFWSClient.Tests/MFWSClient.Authentication.cs b/MFaaP.MFWSClient.Tests/MFWSClient.Authentication.cs
index 4fa2604..aed0fd7 100644
--- a/MFaaP.MFWSClient.Tests/MFWSClient.Authentication.cs
+++ b/MFaaP.MFWSClient.Tests/MFWSClient.Authentication.cs
@@ -36,7 +36,7 @@ public void AuthenticateUsingSingleSignOn()
             {
                 var options = new RestClientOptions();
                 options.BaseUrl = runner.RestClientMock.Object.BaseUrl;
-                runner.RestClientMock.Setup(m => m.Options).Returns(options);
+                runner.RestClientMock.Setup(m => m.Options).Returns(new ReadOnlyRestClientOptions(options));
                 var cookieContainer = new CookieContainer();
                 runner.RestClientMock.Setup(m => m.CookieContainer).Returns(cookieContainer);
             }
@@ -110,7 +110,7 @@ public async Task AuthenticateUsingSingleSignOnAsync()
             {
                 var options = new RestClientOptions();
                 options.BaseUrl = runner.RestClientMock.Object.BaseUrl;
-                runner.RestClientMock.Setup(m => m.Options).Returns(options);
+                runner.RestClientMock.Setup(m => m.Options).Returns(new ReadOnlyRestClientOptions(options));
                 var cookieContainer = new CookieContainer();
                 runner.RestClientMock.Setup(m => m.CookieContainer).Returns(cookieContainer);
             }
diff --git a/MFaaP.MFWSClient.Tests/MFWSClient.cs b/MFaaP.MFWSClient.Tests/MFWSClient.cs
index d5915fe..2c57952 100644
--- a/MFaaP.MFWSClient.Tests/MFWSClient.cs
+++ b/MFaaP.MFWSClient.Tests/MFWSClient.cs
@@ -89,7 +89,7 @@ public static MFaaP.MFWSClient.MFWSClient GetMFWSClient(Moq.Mock<IRestClient> re
 			// Ensure that we have a default parameter collection, if it's not been mocked already.
 			if (null == restClientMoq.Object.DefaultParameters)
 			{
-                var defaultParameters = new ParametersCollection();
+                var defaultParameters = new DefaultParameters(new ReadOnlyRestClientOptions(new RestClientOptions()));
                 restClientMoq
                     .SetupGet(p => p.DefaultParameters)
 					.Returns(defaultParameters);
diff --git a/MFaaP.MFWSClient.Tests/MFWSVaultObjectFileOperations.cs b/MFaaP.MFWSClient.Tests/MFWSVaultObjectFileOperations.cs
index 85a8dda..39e2697 100644
--- a/MFaaP.MFWSClient.Tests/MFWSVaultObjectFileOperations.cs
+++ b/MFaaP.MFWSClient.Tests/MFWSVaultObjectFileOperations.cs
@@ -423,14 +423,14 @@ public async Task AddFilesAsync_CorrectResource()
                 // Return a mock response.
                 .Returns(() =>
                 {
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<ExtendedObjectVersion>>
-                        (
-                            m => m.Data == new ExtendedObjectVersion()
-                        )
-                    );
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<ExtendedObjectVersion>(new RestRequest())
+						{
+							Data = new ExtendedObjectVersion()
+						}
+					);
                 });
 
             // We also need to handle the upload file call or our tests will except.
@@ -439,17 +439,17 @@ public async Task AddFilesAsync_CorrectResource()
                 // Return a mock response.
                 .Returns(() =>
                 {
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<UploadInfo>>
-                        (
-                            m => m.Data == new UploadInfo()
-                            {
-                                UploadID = 1
-                            }
-                        )
-                    );
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<UploadInfo>(new RestRequest())
+						{
+							Data = new UploadInfo()
+							{
+								UploadID = 1
+							}
+						}
+					);
                 });
 
             /* Act */
@@ -498,14 +498,14 @@ public void AddFiles_CorrectResource()
                 })
                 // Return a mock response.
                 .Returns(() =>
-                {
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<ExtendedObjectVersion>>
-                        (
-                            m => m.Data == new ExtendedObjectVersion()
-                        )
-                    );
+				{
+					return Task.FromResult
+					(
+						new RestResponse<ExtendedObjectVersion>(new RestRequest())
+						{
+							Data = new ExtendedObjectVersion()
+						}
+					);
                 });
 
             // We also need to handle the upload file call or our tests will except.
@@ -514,17 +514,17 @@ public void AddFiles_CorrectResource()
                 // Return a mock response.
                 .Returns(() =>
                 {
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<UploadInfo>>
-                        (
-                            m => m.Data == new UploadInfo()
-                            {
-                                UploadID = 1
-                            }
-                        )
-                    );
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<UploadInfo>(new RestRequest())
+						{
+							Data = new UploadInfo()
+							{
+								UploadID = 1
+							}
+						}
+					);
                 });
 
 
@@ -578,14 +578,14 @@ public async Task AddFilesAsync_CorrectMethod()
                 // Return a mock response.
                 .Returns(() =>
                 {
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<ExtendedObjectVersion>>
-                        (
-                            m => m.Data == new ExtendedObjectVersion()
-                        )
-                    );
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<ExtendedObjectVersion>(new RestRequest())
+						{
+							Data = new ExtendedObjectVersion()
+						}
+					);
                 });
 
             // We also need to handle the upload file call or our tests will except.
@@ -594,17 +594,17 @@ public async Task AddFilesAsync_CorrectMethod()
                 // Return a mock response.
                 .Returns(() =>
                 {
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<UploadInfo>>
-                        (
-                            m => m.Data == new UploadInfo()
-                            {
-                                UploadID = 1
-                            }
-                        )
-                    );
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<UploadInfo>(new RestRequest())
+						{
+							Data = new UploadInfo()
+							{
+								UploadID = 1
+							}
+						}
+					);
                 });
 
             /* Act */
@@ -657,10 +657,10 @@ public void AddFiles_CorrectMethod()
                     //Return the mock object.
                     return Task.FromResult
                     (
-                        Mock.Of<RestResponse<ExtendedObjectVersion>>
-                        (
-                            m => m.Data == new ExtendedObjectVersion()
-                        )
+                        new RestResponse<ExtendedObjectVersion>(new RestRequest())
+                        {
+                            Data = new ExtendedObjectVersion()
+                        }
                     );
                 });
 
@@ -670,17 +670,17 @@ public void AddFiles_CorrectMethod()
                 // Return a mock response.
                 .Returns(() =>
                 {
-                    //Return the mock object.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<UploadInfo>>
-                        (
-                            m => m.Data == new UploadInfo()
-                            {
-                                UploadID = 1
-                            }
-                        )
-                    );
+					//Return the mock object.
+					return Task.FromResult
+					(
+						new RestResponse<UploadInfo>(new RestRequest())
+						{
+							Data = new UploadInfo()
+							{
+								UploadID = 1
+							}
+						}
+					);
                 });
 
             /* Act */
@@ -830,14 +830,14 @@ public void RemoveFile_CorrectResource()
                 // Return a mock response.
                 .Returns(() =>
                 {
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<ExtendedObjectVersion>>
-                        (
-                            m => m.Data == new ExtendedObjectVersion()
-                        )
-                    );
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<ExtendedObjectVersion>(new RestRequest())
+						{
+							Data = new ExtendedObjectVersion()
+						}
+					);
                 });
 
 
@@ -881,14 +881,14 @@ public async Task RemoveFileAsync_CorrectResource()
                 // Return a mock response.
                 .Returns(() =>
                 {
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<ExtendedObjectVersion>>
-                        (
-                            m => m.Data == new ExtendedObjectVersion()
-                        )
-                    );
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<ExtendedObjectVersion>(new RestRequest())
+						{
+							Data = new ExtendedObjectVersion()
+						}
+					);
                 });
 
 
diff --git a/MFaaP.MFWSClient.Tests/MFWSVaultObjectSearchOperations.cs b/MFaaP.MFWSClient.Tests/MFWSVaultObjectSearchOperations.cs
index 9143a03..11b3aa3 100644
--- a/MFaaP.MFWSClient.Tests/MFWSVaultObjectSearchOperations.cs
+++ b/MFaaP.MFWSClient.Tests/MFWSVaultObjectSearchOperations.cs
@@ -670,13 +670,12 @@ public void SearchForObjectsByConditions_DatePropertyValueSearchCondition_Correc
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
+					return Task.FromResult
 					(
-						Mock.Of<RestResponse<Results<ObjectVersion>>>
-						(
-							m => m.Data == new Results<ObjectVersion>()
-						)
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
 					);
 				});
 
@@ -721,15 +720,15 @@ public async Task SearchForObjectsByConditionsAsync_DatePropertyValueSearchCondi
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -772,15 +771,15 @@ public void SearchForObjectsByConditions_DatePropertyValueSearchCondition_Correc
 				// Return a mock response.
 				.Returns(() =>
                 {
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -827,15 +826,15 @@ public async Task SearchForObjectsByConditionsAsync_LookupPropertyValueSearchCon
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -878,15 +877,15 @@ public void SearchForObjectsByConditions_LookupPropertyValueSearchCondition_Corr
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -933,15 +932,15 @@ public async Task SearchForObjectsByConditionsAsync_MultiSelectLookupPropertyVal
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -984,15 +983,15 @@ public void SearchForObjectsByConditions_MultiSelectLookupPropertyValueSearchCon
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -1039,15 +1038,15 @@ public async Task SearchForObjectsByConditionsAsync_TextPropertyValueSearchCondi
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -1090,15 +1089,15 @@ public void SearchForObjectsByConditions_TextPropertyValueSearchCondition_Correc
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -1141,15 +1140,15 @@ public async Task SearchForObjectsByConditionsAsync_TextPropertyValueSearchCondi
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -1192,15 +1191,15 @@ public void SearchForObjectsByConditions_TextPropertyValueSearchCondition_Correc
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -1243,15 +1242,15 @@ public async Task SearchForObjectsByConditionsAsync_TextPropertyValueSearchCondi
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -1294,15 +1293,15 @@ public void SearchForObjectsByConditions_TextPropertyValueSearchCondition_Correc
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -1345,15 +1344,15 @@ public async Task SearchForObjectsByConditionsAsync_TextPropertyValueSearchCondi
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -1396,15 +1395,15 @@ public void SearchForObjectsByConditions_TextPropertyValueSearchCondition_Correc
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -1451,15 +1450,15 @@ public async Task SearchForObjectsByConditionsAsync_ValueList_CorrectResource_In
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -1502,15 +1501,15 @@ public void SearchForObjectsByConditionsAsync_ValueList_CorrectResource_External
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<Results<ObjectVersion>>>
-                        (
-                            m => m.Data == new Results<ObjectVersion>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<Results<ObjectVersion>>(new RestRequest())
+						{
+							Data = new Results<ObjectVersion>()
+						}
+					);
+				});
 
 			/* Act */
 
diff --git a/MFaaP.MFWSClient.Tests/MFWSVaultPropertyDefOperations.cs b/MFaaP.MFWSClient.Tests/MFWSVaultPropertyDefOperations.cs
index f5597ad..0baff9f 100644
--- a/MFaaP.MFWSClient.Tests/MFWSVaultPropertyDefOperations.cs
+++ b/MFaaP.MFWSClient.Tests/MFWSVaultPropertyDefOperations.cs
@@ -126,16 +126,15 @@ public async Task GetPropertyDefsAsync_CorrectResource()
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<List<PropertyDef>>>
-                        (
-                            m => m.Data == new List<PropertyDef>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<List<PropertyDef>>(new RestRequest())
+						{
+							Data = new List<PropertyDef>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -178,16 +177,15 @@ public void GetPropertyDefs_CorrectResource()
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<List<PropertyDef>>>
-                        (
-                            m => m.Data == new List<PropertyDef>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<List<PropertyDef>>(new RestRequest())
+						{
+							Data = new List<PropertyDef>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -230,16 +228,15 @@ public async Task GetPropertyDefsAsync_CorrectMethod()
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<List<PropertyDef>>>
-                        (
-                            m => m.Data == new List<PropertyDef>()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<List<PropertyDef>>(new RestRequest())
+						{
+							Data = new List<PropertyDef>()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -282,14 +279,14 @@ public void GetPropertyDefs_CorrectMethod()
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<List<PropertyDef>>>
-                        (
-                            m => m.Data == new List<PropertyDef>()
-                        )
-                    );
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<List<PropertyDef>>(new RestRequest())
+						{
+							Data = new List<PropertyDef>()
+						}
+					);
 				});
 
 			/* Act */
@@ -337,15 +334,15 @@ public async Task GetPropertyDefAsync_CorrectResource()
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<PropertyDef>>
-                        (
-                            m => m.Data == new PropertyDef()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<PropertyDef>(new RestRequest())
+						{
+							Data = new PropertyDef()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -388,15 +385,15 @@ public void GetPropertyDef_CorrectResource()
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<PropertyDef>>
-                        (
-                            m => m.Data == new PropertyDef()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<PropertyDef>(new RestRequest())
+						{
+							Data = new PropertyDef()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -439,15 +436,15 @@ public async Task GetPropertyDefAsync_CorrectMethod()
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<PropertyDef>>
-                        (
-                            m => m.Data == new PropertyDef()
-                        )
-                    );
-                });
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<PropertyDef>(new RestRequest())
+						{
+							Data = new PropertyDef()
+						}
+					);
+				});
 
 			/* Act */
 
@@ -490,14 +487,14 @@ public void GetPropertyDef_CorrectMethod()
 				// Return a mock response.
 				.Returns(() =>
 				{
-                    // Create the mock response.
-                    return Task.FromResult
-                    (
-                        Mock.Of<RestResponse<PropertyDef>>
-                        (
-                            m => m.Data == new PropertyDef()
-                        )
-                    );
+					// Create the mock response.
+					return Task.FromResult
+					(
+						new RestResponse<PropertyDef>(new RestRequest())
+						{
+							Data = new PropertyDef()
+						}
+					);
 				});
 
 			/* Act */
diff --git a/MFaaP.MFWSClient.Tests/MFaaP.MFWSClient.Tests.csproj b/MFaaP.MFWSClient.Tests/MFaaP.MFWSClient.Tests.csproj
index 74e1232..6f54d9f 100644
--- a/MFaaP.MFWSClient.Tests/MFaaP.MFWSClient.Tests.csproj
+++ b/MFaaP.MFWSClient.Tests/MFaaP.MFWSClient.Tests.csproj
@@ -74,6 +74,7 @@
     <Compile Include="MFWSVaultObjectSearchOperations.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="RestApiTestRunner.cs" />
+    <Compile Include="Setup.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\MFaaP.MFWSClient\MFaaP.MFWSClient.csproj">
@@ -83,13 +84,13 @@
   </ItemGroup>
   <ItemGroup>
     <PackageReference Include="Moq">
-      <Version>4.7.1</Version>
+      <Version>4.20.72</Version>
     </PackageReference>
     <PackageReference Include="Newtonsoft.Json">
-      <Version>13.0.1</Version>
+      <Version>13.0.3</Version>
     </PackageReference>
     <PackageReference Include="RestSharp">
-      <Version>108.0.2</Version>
+      <Version>112.0.0</Version>
     </PackageReference>
   </ItemGroup>
   <Choose>
diff --git a/MFaaP.MFWSClient.Tests/RestApiTestRunner.cs b/MFaaP.MFWSClient.Tests/RestApiTestRunner.cs
index ef6ff84..db37b38 100644
--- a/MFaaP.MFWSClient.Tests/RestApiTestRunner.cs
+++ b/MFaaP.MFWSClient.Tests/RestApiTestRunner.cs
@@ -249,14 +249,14 @@ protected virtual void HandleCallback(RestRequest r)
             if (null != this.ExpectedRequestBody)
 			{
                 // Get the body from the request.
-                var requestBody = (r.Parameters ?? new ParametersCollection())
+                var requestBody = (r.Parameters ?? new RequestParameters())
                     .FirstOrDefault(p => p.Type == ParameterType.RequestBody);
 				if (null == requestBody)
 					Assert.Fail("A request body was expected but none was provided.");
 
 				// Ensure the content type is correct.
 				Assert.AreEqual(
-					this.ExpectedRequestBody.Name,
+					this.ExpectedRequestBody.ContentType,
 					requestBody.ContentType);
 
 				// Ensure that the value is correct.
@@ -364,16 +364,15 @@ public RestApiTestRunner(RestSharp.Method expectedMethod,
 		/// <inheritdoc />
 		public new Task<RestResponse<T>> HandleReturns(RestRequest r)
 		{
+			var result = new RestResponse<T>(r)
+			{
+				Data = this.ResponseData,
+				StatusCode = this.ResponseStatusCode,
+				ResponseUri = new Uri(r.Resource, UriKind.Relative)
+			};
+
 			// Create the mock response.
-			return Task.FromResult
-			(
-				Mock.Of<RestResponse<T>>
-				(
-					m => m.Data == this.ResponseData
-					&& m.StatusCode == this.ResponseStatusCode
-					&& m.ResponseUri == new Uri(r.Resource, UriKind.Relative)
-				)
-			);
+			return Task.FromResult(result);
 
 		}
 	}
diff --git a/MFaaP.MFWSClient.Tests/Setup.cs b/MFaaP.MFWSClient.Tests/Setup.cs
new file mode 100644
index 0000000..9501bd1
--- /dev/null
+++ b/MFaaP.MFWSClient.Tests/Setup.cs
@@ -0,0 +1,58 @@
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace MFaaP.MFWSClient.Tests
+{
+	[TestClass]
+	public class SetupAssemblyInitializer
+	{
+		[AssemblyInitialize]
+		public static void AssemblyInit(TestContext context)
+		{
+			var assemblies = new List<string>()
+			{
+				"System.Text.Json",
+				"System.Runtime.CompilerServices.Unsafe"
+			};
+			var assemlbyResolveHelper = new AssemblyResolveHelper(assemblies);
+			AppDomain.CurrentDomain.AssemblyResolve += assemlbyResolveHelper.OnAssemlbyResolve;
+		}
+	}
+	public class AssemblyResolveHelper
+	{
+		public AssemblyResolveHelper(string assemblyName)
+		{
+			_assemlbyNames.Add(assemblyName);
+		}
+
+		public AssemblyResolveHelper(List<string> assemblyNames)
+		{
+			if (assemblyNames != null)
+			{
+				_assemlbyNames = assemblyNames;
+			}
+		}
+
+		private List<string> _assemlbyNames = new List<string>();
+
+		public System.Reflection.Assembly OnAssemlbyResolve(object sender, ResolveEventArgs args)
+		{
+			var assemblyName = _assemlbyNames.FirstOrDefault(i => i == args.Name.Split(',')[0]);
+			if (assemblyName != null)
+			{
+				string assemlbyPath = Path.Combine(Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location), assemblyName + ".dll");
+
+				if (File.Exists(assemlbyPath))
+				{
+					return System.Reflection.Assembly.LoadFrom(assemlbyPath);
+				}
+			}
+			return null;
+		}
+	}
+}
diff --git a/MFaaP.MFWSClient/MFWSClient.Authentication.cs b/MFaaP.MFWSClient/MFWSClient.Authentication.cs
index b201189..b41d156 100644
--- a/MFaaP.MFWSClient/MFWSClient.Authentication.cs
+++ b/MFaaP.MFWSClient/MFWSClient.Authentication.cs
@@ -43,7 +43,7 @@ public string AuthenticationToken
 				foreach (var parameter in this.DefaultParameters.Where(p => p.Name == MFWSClient.XAuthenticationHttpHeaderName)
 					.ToArray())
 				{
-					this.DefaultParameters.RemoveParameter(parameter);
+					this.DefaultParameters.RemoveParameter(parameter.Name, parameter.Type);
 				}
 
 				// Add the new one.
@@ -81,7 +81,7 @@ public void ClearVaultHeader()
 			foreach (var parameter in this.DefaultParameters.Where(p => p.Name == MFWSClient.VaultHttpHeaderName)
 				.ToArray())
 			{
-				this.DefaultParameters.RemoveParameter(parameter);
+				this.DefaultParameters.RemoveParameter(parameter.Name, parameter.Type);
 			}
 		}
 
@@ -110,7 +110,7 @@ protected virtual void ClearAuthenticationToken()
 				foreach (var parameter in this.DefaultParameters.Where(p => p.Name == MFWSClient.AuthorizationHttpHeaderName)
 					.ToArray())
 				{
-					this.DefaultParameters.RemoveParameter(parameter);
+					this.DefaultParameters.RemoveParameter(parameter.Name, parameter.Type);
 				}
 		}
 
diff --git a/MFaaP.MFWSClient/MFWSClientBase.HttpRequests.cs b/MFaaP.MFWSClient/MFWSClientBase.HttpRequests.cs
index 2aed321..f54db2d 100644
--- a/MFaaP.MFWSClient/MFWSClientBase.HttpRequests.cs
+++ b/MFaaP.MFWSClient/MFWSClientBase.HttpRequests.cs
@@ -403,7 +403,7 @@ public virtual void EnsureEnabledExtensionsAreSpecified(RestRequest request)
 
 			// Retrieve the current X-Extensions values (comma-separated) as an array.
 			// Need to handle various null/empty scenarios here.
-			var existingExtensions = ((request.Parameters ?? new ParametersCollection())
+			var existingExtensions = ((request.Parameters ?? new RequestParameters())
 										.FirstOrDefault(p =>
 											p.Type == ParameterType.HttpHeader
 											&& p.Name == MFWSClientBase.ExtensionsHttpHeaderName)?
diff --git a/MFaaP.MFWSClient/MFWSClientBase.cs b/MFaaP.MFWSClient/MFWSClientBase.cs
index dabf4ab..01b467b 100644
--- a/MFaaP.MFWSClient/MFWSClientBase.cs
+++ b/MFaaP.MFWSClient/MFWSClientBase.cs
@@ -11,13 +11,13 @@ namespace MFaaP.MFWSClient
 	public interface IRestClient
 	{
 		CookieContainer CookieContainer { get; }
-		ParametersCollection DefaultParameters { get; }
+		DefaultParameters DefaultParameters { get; }
         Task<RestResponse> ExecuteAsync(RestRequest request, CancellationToken cancellationToken = default);
         Task<RestResponse<T>> ExecuteAsync<T>(RestRequest request, CancellationToken cancellationToken = default);
-        bool FollowRedirects { get; set; }
-		bool PreAuthenticate { get; set; }
-		RestClientOptions Options { get; }
-		Uri BaseUrl { get; set; }
+        bool FollowRedirects { get; }
+		bool PreAuthenticate { get; }
+		ReadOnlyRestClientOptions Options { get; }
+		Uri BaseUrl { get; }
 	}
 	public class RestSharpRestClient
 		: RestClient, IRestClient
@@ -25,7 +25,6 @@ public class RestSharpRestClient
         public RestSharpRestClient(Uri baseUri)
             : base(baseUri)
         {
-
         }
 
 		public RestSharpRestClient(RestClientOptions options)
@@ -47,21 +46,23 @@ public Task<RestResponse<T>> ExecuteAsync<T>(RestRequest request, CancellationTo
 			return RestClientExtensions.ExecuteAsync<T>(this, request, request.Method, cancellationToken);
 		}
 
+		public CookieContainer CookieContainer
+		{
+			get => base.Options?.CookieContainer;
+		}
+
 		public Uri BaseUrl
 		{
 			get => base.Options?.BaseUrl;
-			set => base.Options.BaseUrl = value;
 		}
 
-        public bool FollowRedirects
+		public bool FollowRedirects
 		{
 			get => base.Options.FollowRedirects;
-			set => base.Options.FollowRedirects = value;
 		}
 		public bool PreAuthenticate
         {
             get => base.Options.PreAuthenticate;
-            set => base.Options.PreAuthenticate = value;
         }
     }
 	/// <summary>
@@ -115,7 +116,7 @@ public CookieContainer CookieContainer
         /// <summary>
         /// The default parameters for all http requests.
         /// </summary>
-        public ParametersCollection DefaultParameters
+        public DefaultParameters DefaultParameters
         {
             get { return this.RestClient.DefaultParameters; }
         }
@@ -215,8 +216,6 @@ protected MFWSClientBase(IRestClient restClient)
 			// Set up the RestClient.
 			this.RestClient = restClient
 				?? throw new ArgumentNullException(nameof(restClient));
-            this.RestClient.FollowRedirects = true;
-            this.RestClient.PreAuthenticate = true;
 
             // Set up our sub-objects.
             this.ObjectSearchOperations = new MFWSVaultObjectSearchOperations(this);
@@ -245,26 +244,41 @@ protected MFWSClientBase(IRestClient restClient)
         protected MFWSClientBase(string baseUrl)
             : this(new Uri(baseUrl))
         {
-        }
+		}
 
-        /// <summary>
-        /// Creates an MFWSClient pointing at the MFWA site.
-        /// </summary>
-        /// <param name="baseUrl">The base url of the MFWA (web access) site; note that this should be of the form
-        /// "http://localhost", not of the form "http://localhost/REST".</param>
-        protected MFWSClientBase(Uri baseUrl)
-            : this(new RestSharpRestClient(baseUrl))
-        {
-        }
+		/// <summary>
+		/// Creates an MFWSClient pointing at the MFWA site.
+		/// </summary>
+		/// <param name="baseUrl">The base url of the MFWA (web access) site; note that this should be of the form
+		/// "http://localhost", not of the form "http://localhost/REST".</param>
+		protected MFWSClientBase(Uri baseUrl)
+			: this(new RestClientOptions()
+			{
+				BaseUrl = baseUrl,
+				FollowRedirects = true,
+				PreAuthenticate = true
+			})
+		{
+		}
 
-        /// <summary>
-        /// Adds a default header to requests.
-        /// </summary>
-        /// <param name="name">The name of the HTTP header.</param>
-        /// <param name="value">The value of the HTTP header.</param>
-        public void AddDefaultHeader(string name, string value)
+		/// <summary>
+		/// Creates an MFWSClient pointing at the MFWA site.
+		/// </summary>
+		/// <param name="baseUrl">The base url of the MFWA (web access) site; note that this should be of the form
+		/// "http://localhost", not of the form "http://localhost/REST".</param>
+		protected MFWSClientBase(RestClientOptions options)
+			: this(new RestSharpRestClient(options ?? new RestClientOptions()))
+		{
+		}
+
+		/// <summary>
+		/// Adds a default header to requests.
+		/// </summary>
+		/// <param name="name">The name of the HTTP header.</param>
+		/// <param name="value">The value of the HTTP header.</param>
+		public void AddDefaultHeader(string name, string value)
 		{
-			try { this.RestClient.DefaultParameters.RemoveParameter(name); }
+			try { this.RestClient.DefaultParameters.RemoveParameter(name, ParameterType.HttpHeader); }
 			catch{ }
 
 			this.RestClient.DefaultParameters.AddParameter(new HeaderParameter(name, value));
@@ -282,7 +296,7 @@ public void ClearPresharedKey()
 				.ToArray();
 			foreach (var existingHeader in existingHeaders)
 			{
-				this.RestClient.DefaultParameters.RemoveParameter(existingHeader);
+				this.RestClient.DefaultParameters.RemoveParameter(existingHeader.Name, existingHeader.Type);
 			}
 		}
 
@@ -320,7 +334,7 @@ public void SetAcceptLanguage(string acceptLanguages)
 				.ToArray();
 			foreach (var existingHeader in existingHeaders)
 			{
-				this.RestClient.DefaultParameters.RemoveParameter(existingHeader);
+				this.RestClient.DefaultParameters.RemoveParameter(existingHeader.Name, existingHeader.Type);
 			}
 
 			// Sanity.
diff --git a/MFaaP.MFWSClient/MFaaP.MFWSClient.csproj b/MFaaP.MFWSClient/MFaaP.MFWSClient.csproj
index 80d2eaa..8173278 100644
--- a/MFaaP.MFWSClient/MFaaP.MFWSClient.csproj
+++ b/MFaaP.MFWSClient/MFaaP.MFWSClient.csproj
@@ -17,7 +17,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="RestSharp" Version="108.0.2" />
+    <PackageReference Include="RestSharp" Version="112.0.0" />
   </ItemGroup>
   
   <PropertyGroup>