diff --git a/source/Platform/Unix/X11Display.cpp b/source/Platform/Unix/X11Display.cpp
index e8e5770..1f5144c 100644
--- a/source/Platform/Unix/X11Display.cpp
+++ b/source/Platform/Unix/X11Display.cpp
@@ -126,7 +126,20 @@ void X11Display::setSize(unsigned int width, unsigned int height)
 
 Vector2u X11Display::getSize() const
 {
-	return m_size;
+	int x, y;
+	unsigned int w, h, bw, d;
+	::Display* disp   = Xlib::getDisplay();
+	::Window ancestor = m_win;
+    	::Window root     = DefaultRootWindow(disp);
+
+	while (Xlib::getParentWindow(ancestor) != root) {
+		// Next window up (parent window).
+		ancestor = Xlib::getParentWindow(ancestor);
+	}
+
+	::XGetGeometry(disp, ancestor, &root, &x, &y, &w, &h, &bw, &d);
+
+	return Vector2u(w, h);
 }
 
 void X11Display::setPosition(unsigned int x, unsigned int y)