diff --git a/samples/99_svmunmap/CMakeLists.txt b/samples/99_svmunmap/CMakeLists.txt
new file mode 100644
index 0000000..be549b0
--- /dev/null
+++ b/samples/99_svmunmap/CMakeLists.txt
@@ -0,0 +1,10 @@
+# Copyright (c) 2023 Ben Ashbaugh
+#
+# SPDX-License-Identifier: MIT
+
+add_opencl_sample(
+    TEST
+    NUMBER 99
+    TARGET svmunmap
+    VERSION 200
+    SOURCES main.cpp)
diff --git a/samples/99_svmunmap/main.cpp b/samples/99_svmunmap/main.cpp
new file mode 100644
index 0000000..c5ac69b
--- /dev/null
+++ b/samples/99_svmunmap/main.cpp
@@ -0,0 +1,71 @@
+/*
+// Copyright (c) 2023 Ben Ashbaugh
+//
+// SPDX-License-Identifier: MIT
+*/
+
+#include <popl/popl.hpp>
+
+#include <CL/opencl.hpp>
+
+const size_t    gwx = 1024*1024;
+
+int main(
+    int argc,
+    char** argv )
+{
+    int platformIndex = 0;
+    int deviceIndex = 0;
+
+    {
+        popl::OptionParser op("Supported Options");
+        op.add<popl::Value<int>>("p", "platform", "Platform Index", platformIndex, &platformIndex);
+        op.add<popl::Value<int>>("d", "device", "Device Index", deviceIndex, &deviceIndex);
+
+        bool printUsage = false;
+        try {
+            op.parse(argc, argv);
+        } catch (std::exception& e) {
+            fprintf(stderr, "Error: %s\n\n", e.what());
+            printUsage = true;
+        }
+
+        if (printUsage || !op.unknown_options().empty() || !op.non_option_args().empty()) {
+            fprintf(stderr,
+                "Usage: copybuffer [options]\n"
+                "%s", op.help().c_str());
+            return -1;
+        }
+    }
+
+    std::vector<cl::Platform> platforms;
+    cl::Platform::get(&platforms);
+
+    printf("Running on platform: %s\n",
+        platforms[platformIndex].getInfo<CL_PLATFORM_NAME>().c_str() );
+
+    std::vector<cl::Device> devices;
+    platforms[platformIndex].getDevices(CL_DEVICE_TYPE_ALL, &devices);
+
+    printf("Running on device: %s\n",
+        devices[deviceIndex].getInfo<CL_DEVICE_NAME>().c_str() );
+
+    cl::Context context{devices[deviceIndex]};
+    cl::CommandQueue commandQueue = cl::CommandQueue{context, devices[deviceIndex]};
+
+    void* ptr = clSVMAlloc(context(), CL_MEM_READ_WRITE, 1024, 0);
+    printf("clSVMAlloc returned %p\n", ptr);
+
+    cl_event event = nullptr;
+    cl_int errorCode = clEnqueueSVMUnmap(
+        commandQueue(),
+        ptr,
+        0,
+        nullptr,
+        &event);
+    printf("clEnqueueSVMUnmap returned %d, event is %p.\n", errorCode, event);
+    clReleaseEvent(event);
+
+    clSVMFree(context(), ptr);
+    return 0;
+}
diff --git a/samples/CMakeLists.txt b/samples/CMakeLists.txt
index 65cbd34..2169021 100644
--- a/samples/CMakeLists.txt
+++ b/samples/CMakeLists.txt
@@ -90,6 +90,8 @@ add_subdirectory( 06_ndrangekernelfromfile )
 
 add_subdirectory( 10_queueexperiments )
 
+add_subdirectory( 99_svmunmap )
+
 set(BUILD_EXTENSION_SAMPLES TRUE)
 if(NOT TARGET OpenCLExt)
     message(STATUS "Skipping Extension Samples - OpenCL Extension Loader is not found.")