#DEFINE GWL_EXSTYLE -20 #DEFINE WS_EX_LAYERED 524288 #DEFINE LWA_COLORKEY 1 #DEFINE LWA_ALPHA 2 DECLARE INTEGER FindWindow IN WIN32API STRING, STRING DECLARE LONG GetWindowLong IN WIN32API INTEGER, INTEGER DECLARE LONG SetWindowLong IN WIN32API INTEGER, INTEGER, LONG DECLARE SetLayeredWindowAttributes IN WIN32API INTEGER, INTEGER, INTEGER, LONG * Getting a window handle hWnd = FindWindow(NULL, 'Microsoft Visual FoxPro') attr = GetWindowLong(hWnd, GWL_EXSTYLE) SetWindowLong(hWnd, GWL_EXSTYLE, attr + WS_EX_LAYERED) * To make the whole window semi-transparent: Alpha = 192 && 0-255, 0 - transparent SetLayeredWindowAttributes(hWnd, 0, Alpha, LWA_ALPHA) * To make a selected color transparent: *Color = RGB(255,255,255) *SetLayeredWindowAttributes(hWnd, Color, 0, LWA_COLORKEY)