diff --git a/src/Lumper.UI/App.axaml.cs b/src/Lumper.UI/App.axaml.cs
index 22bf68a3..8d111cbe 100644
--- a/src/Lumper.UI/App.axaml.cs
+++ b/src/Lumper.UI/App.axaml.cs
@@ -1,5 +1,6 @@
 using Avalonia;
 using Avalonia.Controls.ApplicationLifetimes;
+using Avalonia.Input;
 using Avalonia.Markup.Xaml;
 using Lumper.UI.ViewModels;
 using Lumper.UI.Views;
@@ -17,11 +18,22 @@ public override void OnFrameworkInitializationCompleted()
     {
         if (ApplicationLifetime is IClassicDesktopStyleApplicationLifetime
             desktop)
+        {
+            var vm = new MainWindowViewModel();
             desktop.MainWindow = new MainWindow
             {
-                DataContext = new MainWindowViewModel()
+                DataContext = vm,
             };
 
+            desktop.MainWindow.AddHandler(DragDrop.DragOverEvent, MainWindowViewModel.DragOver);
+            desktop.MainWindow.AddHandler(DragDrop.DropEvent, vm.Drop);
+
+            if (desktop.Args?.Length > 0)
+            {
+                vm.LoadBsp(desktop.Args[0]);
+            }
+        }
+
         base.OnFrameworkInitializationCompleted();
     }
 }
diff --git a/src/Lumper.UI/ViewModels/MainWindowViewModel.IO.cs b/src/Lumper.UI/ViewModels/MainWindowViewModel.IO.cs
index 5f3199a5..96d2c51e 100644
--- a/src/Lumper.UI/ViewModels/MainWindowViewModel.IO.cs
+++ b/src/Lumper.UI/ViewModels/MainWindowViewModel.IO.cs
@@ -148,13 +148,13 @@ private async void Save(string path)
         _bspModel.FilePath = path;
     }
 
-    private void LoadBsp(string path)
+    public void LoadBsp(string path)
     {
         var bspFile = new BspFile(path);
         BspModel = new BspViewModel(this, bspFile);
     }
 
-    private async Task LoadBsp(IStorageFile file)
+    public async Task LoadBsp(IStorageFile file)
     {
         if (!file.CanOpenRead)
             return;
@@ -163,7 +163,7 @@ private async Task LoadBsp(IStorageFile file)
         if(!file.TryGetUri(out var path))
         {
            throw new Exception("Failed to get file path");
-            
+
         }
         LoadBsp(path.AbsolutePath);
     }
diff --git a/src/Lumper.UI/ViewModels/MainWindowViewModel.cs b/src/Lumper.UI/ViewModels/MainWindowViewModel.cs
index c23e767d..72917ff9 100644
--- a/src/Lumper.UI/ViewModels/MainWindowViewModel.cs
+++ b/src/Lumper.UI/ViewModels/MainWindowViewModel.cs
@@ -1,6 +1,10 @@
 using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
 using Avalonia;
 using Avalonia.Controls.ApplicationLifetimes;
+using Avalonia.Input;
 using Lumper.UI.ViewModels.Bsp;
 using ReactiveUI;
 
@@ -45,4 +49,49 @@ public BspNodeBase? SelectedNode
         get => _selectedNode;
         set => this.RaiseAndSetIfChanged(ref _selectedNode, value);
     }
+
+    internal static void DragOver(object? sender, DragEventArgs e)
+    {
+        e.DragEffects = DragDropEffects.Link;
+
+        var names = e.Data.GetFileNames() ?? new List<string>();
+
+        if (!e.Data.Contains(DataFormats.FileNames) || !names.FirstOrDefault("").ToLower().EndsWith(".bsp"))
+            e.DragEffects = DragDropEffects.None;
+    }
+
+    internal void Drop(object? sender, DragEventArgs e)
+    {
+        if (!e.Data.Contains(DataFormats.FileNames))
+            return;
+
+        var names = e.Data.GetFileNames() ?? new List<String>();
+        foreach (string target in names)
+        {
+            if (!target.ToLower().EndsWith(".bsp"))
+                continue;
+
+            if (BspModel == null)
+            {
+                // if nothing is open, open it.
+                LoadBsp(target);
+            }
+            else
+            {
+                // Otherwise, open a brand new Lumper instance with it.
+                string? mainModuleFileName = Process.GetCurrentProcess().MainModule?.FileName;
+                if (mainModuleFileName == null)
+                    return;
+
+                string? executablePath = mainModuleFileName;
+                ProcessStartInfo startInfo = new ProcessStartInfo()
+                {
+                    ArgumentList = { $"{target}" },
+                    FileName = executablePath,
+                };
+
+                Process.Start(startInfo);
+            }
+        }
+    }
 }
diff --git a/src/Lumper.UI/Views/MainWindow.axaml b/src/Lumper.UI/Views/MainWindow.axaml
index f222b67d..90c5c525 100644
--- a/src/Lumper.UI/Views/MainWindow.axaml
+++ b/src/Lumper.UI/Views/MainWindow.axaml
@@ -14,6 +14,7 @@
         TransparencyLevelHint="AcrylicBlur"
         ExtendClientAreaToDecorationsHint="True"
         WindowStartupLocation="CenterScreen"
+        DragDrop.AllowDrop="True"
         Background="Transparent">
 
     <Design.DataContext>