Most of the time, the event-driven nature of GUI programming maintains a good illusion of handling multiple tasks simultaneously. Redrawing a window usually takes a tiny fraction of a second, and user input can be handled rapidly. However, there are times when a task cannot easily be broken down into small chunks handled by a single thread, and this is where multithreaded programming becomes useful. This chapter shows you how threads can be controlled in wxWidgets, and it ends with some alternatives to using threads.