diff --git a/ProjectDirector/ProjectDirector.cs b/ProjectDirector/ProjectDirector.cs
index 5c400ef..b380ff7 100644
--- a/ProjectDirector/ProjectDirector.cs
+++ b/ProjectDirector/ProjectDirector.cs
@@ -77,6 +77,9 @@ internal sealed class ProjectDirector
 	internal ImGuiAppConfig BuildConfig() => new()
 	{
 		Title = "Project Director",
+
+		// The options are loaded by the constructor, so this is the state the last run saved.
+		InitialWindowState = Options.WindowState,
 		OnAppMenu = ShowMenu,
 		OnMoveOrResize = WindowResized,
 		OnRender = Tick,
diff --git a/tests/ProjectDirector.UITests/WindowStateTests.cs b/tests/ProjectDirector.UITests/WindowStateTests.cs
new file mode 100644
index 0000000..37db40d
--- /dev/null
+++ b/tests/ProjectDirector.UITests/WindowStateTests.cs
@@ -0,0 +1,46 @@
+// Copyright (c) 2023-2026 ktsu-dev contributors
+
+namespace ktsu.ProjectDirector.UITests;
+
+using System.IO.Abstractions.TestingHelpers;
+using System.Numerics;
+
+using ktsu.AppDataStorage;
+using ktsu.ImGui.App;
+
+using Silk.NET.Windowing;
+
+/// <summary>
+/// The window's size, position and layout, which the application saves whenever the window moves
+/// or resizes, and starts the next run with.
+/// </summary>
+[TestClass]
+public sealed class WindowStateTests
+{
+	[TestMethod]
+	public void BuildConfig_StartsTheWindowWhereTheSavedOptionsLeftIt()
+	{
+		AppData.ConfigureForTesting(() => new MockFileSystem());
+		try
+		{
+			ImGuiAppWindowState saved = new()
+			{
+				Size = new Vector2(1600, 1000),
+				Pos = new Vector2(2000, 150),
+				LayoutState = WindowState.Maximized,
+			};
+			Assert.AreNotEqual(saved.LayoutState, new ImGuiAppWindowState().LayoutState, "The default layout is already maximized, so this would prove nothing.");
+
+			using ProjectDirectorOptions options = new() { WindowState = saved };
+			ImGuiAppConfig config = new ProjectDirector(options).BuildConfig();
+
+			Assert.AreEqual(saved.Size, config.InitialWindowState.Size);
+			Assert.AreEqual(saved.Pos, config.InitialWindowState.Pos);
+			Assert.AreEqual(saved.LayoutState, config.InitialWindowState.LayoutState);
+		}
+		finally
+		{
+			AppData.ResetFileSystem();
+		}
+	}
+}