If you make the client widget resizable then it will be resized to the scroll area If you want scroll bars to appear, you have to enforce a size on the client widget so that it doesn't fit the scroll area and scroll bars will appear. So basically the client widget has to tell that it cannot be smaller than X but it can be larger than that. If X is lower than the scroll area size then scroll area will enlarge the client to its own size. If X is larger than the scroll area, then scroll bars will appear.