diff --git a/src/gui/symbol/window.cpp b/src/gui/symbol/window.cpp
index 7054e303..79abb4ab 100644
--- a/src/gui/symbol/window.cpp
+++ b/src/gui/symbol/window.cpp
@@ -26,8 +26,11 @@ SymbolWindow::SymbolWindow(Window* parent) {
 }
 
 SymbolWindow::SymbolWindow(Window* parent, const String& filename) {
-	// TODO : open file
-	init(parent, default_symbol());
+	// open file
+	Reader reader(filename);
+	SymbolP symbol;
+	reader.handle(symbol);
+	init(parent, symbol);
 }
 
 SymbolWindow::SymbolWindow(Window* parent, const SymbolValueP& value, const SetP& set)
diff --git a/src/gui/symbol/window.hpp b/src/gui/symbol/window.hpp
index 7f274d14..74ea6f39 100644
--- a/src/gui/symbol/window.hpp
+++ b/src/gui/symbol/window.hpp
@@ -27,7 +27,7 @@ class SymbolWindow : public Frame {
 	SymbolWindow(Window* parent);
 	/// Construct a SymbolWindow showing a symbol from a file
 	SymbolWindow(Window* parent, const String& filename);
-//	/// Construct a SymbolWindow showing a symbol value in a set
+	/// Construct a SymbolWindow showing a symbol value in a set
 	SymbolWindow(Window* parent, const SymbolValueP& value, const SetP& set);
 	
   private:
diff --git a/src/main.cpp b/src/main.cpp
index b55b0501..ab8d7450 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -48,17 +48,35 @@ bool MSE::OnInit() {
 		packages.init();
 		settings.read();
 		the_locale = Locale::byName(settings.locale);
-		// check for updates
 		check_updates();
-		//Window* wnd = new SymbolWindow(nullptr);
-		//GameP g = Game::byName(_("magic"))
-		SetP  s = new_shared<Set>();
-		s->open(_("test.mse-set"));
-		Window* wnd = new SetWindow(nullptr, s);
-		//Window* wnd = new WelcomeWindow();
-		wnd->Show();
+		
+		// interpret command line
+		if (argc > 1) {
+			try {
+				// Command line argument, find its extension
+				wxFileName f(argv[1]);
+				if (f.GetExt() == _("mse-symbol")) {
+					// Show the symbol editor
+					Window* wnd = new SymbolWindow(nullptr, argv[1]);
+					wnd->Show();
+					return true;
+				} else if (f.GetExt() == _("mse-set") || f.GetExt() == _("mse") || f.GetExt() == _("set")) {
+					// Show the set window
+					Window* wnd = new SetWindow(nullptr, import_set(argv[1]));
+					wnd->Show();
+					return true;
+				} else {
+					handle_error(_("Invalid command line argument:\n") + String(argv[1]));
+				}
+			} catch (const Error& e) {
+				handle_error(e);
+			}
+		}
+		
+		// no command line arguments, or error, show welcome window
+		(new WelcomeWindow())->Show();
 		return true;
-	
+			
 	} catch (Error e) {
 		handle_error(e, false);
 	} catch (std::exception e) {
@@ -67,7 +85,7 @@ bool MSE::OnInit() {
 	} catch (...) {
 		handle_error(InternalError(_("An unexpected exception occurred!")), false);
 	}
-	packages.destroy();
+	OnExit();
 	return false;
 }