diff --git a/src/EchoHub.Client/AppOrchestrator.cs b/src/EchoHub.Client/AppOrchestrator.cs
index 9ac9b5c..7769d0a 100644
--- a/src/EchoHub.Client/AppOrchestrator.cs
+++ b/src/EchoHub.Client/AppOrchestrator.cs
@@ -27,6 +27,7 @@ public sealed class AppOrchestrator : IDisposable
     private readonly ChatMessageManager _messageManager;
     private readonly CommandHandler _commandHandler;
     private readonly NotificationSoundService _notificationSound;
+    private readonly OsNotificationService _osNotification;
     private readonly AudioPlaybackService _audioPlayback = new();
     private readonly UpdateChecker _updateService;
     private readonly ConnectionManager _conn = new();
@@ -65,6 +66,7 @@ public sealed class AppOrchestrator : IDisposable
         _mainWindow = new MainWindow(app, _messageManager);
         _commandHandler = new CommandHandler();
         _notificationSound = new NotificationSoundService(config.Notifications);
+        _osNotification = new OsNotificationService();
         _updateService = new UpdateChecker(app);
 
         WireMainWindowEvents();
@@ -1105,6 +1107,9 @@ public sealed class AppOrchestrator : IDisposable
                 && message.Content.Contains($"@{_session.Username}", StringComparison.OrdinalIgnoreCase))
             {
                 _ = _notificationSound.PlayAsync();
+                string title = $"Mentioned by {message.SenderDisplayName ?? message.SenderUsername} in #{message.ChannelName}";
+                string body = message.Content.Length > 200 ? message.Content[..200] + "..." : message.Content;
+                _osNotification.Show(title, body);
             }
         };
 
diff --git a/src/EchoHub.Client/EchoHub.Client.csproj b/src/EchoHub.Client/EchoHub.Client.csproj
index 8e4bd85..7b52cb1 100644
--- a/src/EchoHub.Client/EchoHub.Client.csproj
+++ b/src/EchoHub.Client/EchoHub.Client.csproj
@@ -9,6 +9,7 @@
     <PackageReference Include="Microsoft.AspNetCore.SignalR.Client" Version="10.0.3" />
     <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="10.0.3" />
     <PackageReference Include="NetCoreAudio" Version="2.0.1" />
+    <PackageReference Include="OsNotifications" Version="1.1.5" />
     <PackageReference Include="Serilog" Version="4.3.1" />
     <PackageReference Include="Serilog.Settings.Configuration" Version="10.0.0" />
     <PackageReference Include="Serilog.Sinks.File" Version="7.0.0" />
diff --git a/src/EchoHub.Client/Services/OsNotificationService.cs b/src/EchoHub.Client/Services/OsNotificationService.cs
new file mode 100644
index 0000000..3401aeb
--- /dev/null
+++ b/src/EchoHub.Client/Services/OsNotificationService.cs
@@ -0,0 +1,34 @@
+using OsNotifications;
+
+using Serilog;
+
+namespace EchoHub.Client.Services;
+
+public sealed class OsNotificationService
+{
+    static OsNotificationService()
+    {
+        Notifications.SetGuiApplication(true);
+    }
+
+    /// <summary>
+    /// Shows an OS notification with the given title and optional body. 
+    /// </summary>
+    /// <param name="title"></param>
+    /// <param name="body"></param>
+    public void Show(string title, string? body = null)
+    {
+        try
+        {
+            Notifications.ShowNotification(title, body ?? string.Empty);
+        }
+        catch (PlatformNotSupportedException ex)
+        {
+            Log.Warning(ex, "OS notifications not supported on this platform");
+        }
+        catch (Exception ex)
+        {
+            Log.Warning(ex, "Failed to show OS notification");
+        }
+    }
+}