Reading through the backend_wx.py code, I noticed a small deviation from the other interactive backends. All other new_figure_manager_given_figure() separately creates a canvas and manager object (which, in turn, creates the window object) and hooks them all up. The manager would handle all window responsibilities such as creation/destruction and sizing. However, for the WX backend, this function just creates a FigureFrameWx object, which is the window widget. This object also becomes responsible for creating the canvas and the manager. This setup seems a bit backwards to me, but I am not entirely sure. It is definitely different. Does anybody know if it is merely a remnant of older designs (I think WX was the first backend)? What are the limitations of this approach, if any? Is there any interest in normalizing this backend design with the others (or vice versa)? Thanks to everybody for putting up with my questions over the last few months. Oftentimes, just writing out the questions have been very useful to me, along with your responses. The good news is the book is almost done, and I hope that it will be an extremely useful reference. Cheers! Ben Root