diff --git a/SpritePacker-GUI/MainWindow.cs b/SpritePacker-GUI/MainWindow.cs
index 5718984..5c7e665 100644
--- a/SpritePacker-GUI/MainWindow.cs
+++ b/SpritePacker-GUI/MainWindow.cs
@@ -5,6 +5,7 @@ using System.Linq;
 using Gtk;
 using Ext.SilentorBit;
 using System.Drawing.Imaging;
+using System.Runtime.ExceptionServices;
 
 namespace SpritePacker.GUI
 {
@@ -19,6 +20,8 @@ namespace SpritePacker.GUI
 		private Button openImageButton;
 		private Button removeImageButton;
 
+		private SpritePacker spritePacker = new SpritePacker();
+
 		public MainWindow() : base("SpritePacker GUI")
 		{
 			if (!initialised)
@@ -72,17 +75,35 @@ namespace SpritePacker.GUI
 				Filter = spriteListSelectorFilter
 			};
 			spriteListSelector.SelectMultiple = true;
+			spriteListSelector.AddButton("Add Sprites", ResponseType.Ok);
+			spriteListSelector.AddButton("Cancel", ResponseType.Cancel);
 
 			// Create the ListView to display the added sprites
 			spriteListDisplay = new SpriteListView() { Margin = 10, MarginTop = 5 };
 			spriteListDisplay.AddItem(new Sprite("/home/sbrl/Pictures/Spaghetti.png"));
 
-			openImageButton = new Button("Add sprite") { Margin = 10, MarginTop = 0, MarginBottom = 0 };
-			removeImageButton = new Button("Remove Sprite") { Margin = 10, MarginTop = 0, MarginBottom = 0 };
+			openImageButton = new Button("Add Sprites") { Margin = 10, MarginTop = 0, MarginBottom = 0 };
+			removeImageButton = new Button("Remove Selected Sprites") { Margin = 10, MarginTop = 0, MarginBottom = 0 };
+			openImageButton.Released += (object sender, EventArgs e) => {
+				ResponseType response = (ResponseType)spriteListSelector.Run();
+				spriteListSelector.Hide();
+				switch(response)
+				{
+					case ResponseType.Ok:
+						Action_AddSprite(spriteListSelector.Filenames);
+						break;
+					case ResponseType.DeleteEvent:
+					case ResponseType.Cancel:
+						Console.Error.WriteLine("Ignoring sprite file chooser response {0}.", response);
+						break;
+					default:
+						throw new Exception($"Unknown sprite file chooser response type {response}.");
+				}
+			};
 
 			// Populate the control button row
-			controlButtonRow.PackStart(removeImageButton, true, false, 0);
 			controlButtonRow.PackStart(openImageButton, true, false, 0);
+			controlButtonRow.PackStart(removeImageButton, true, false, 0);
 
 			// Populate the left panel
 			leftPanel.PackStart(controlButtonRow, false, false, 5);
@@ -95,6 +116,16 @@ namespace SpritePacker.GUI
 			// Add the master container to the window itself
 			Add(masterContainer);
 		}
+
+		void Action_AddSprite(string[] selectedFilenames)
+		{
+			foreach (string filename in selectedFilenames)
+			{
+				Sprite nextSprite = new Sprite(filename);
+				spritePacker.Add(nextSprite);
+				spriteListDisplay.AddItem(nextSprite);
+			}
+		}
 	}
 }