Abstract: We discuss the design of user interface techniques for visualizing and controlling the recognition of handwritten mathematics. In particular, we present a range of visualization styles for displaying the result of math recognition. These styles offer different trade-offs between ease of user correction of errors in recognition and impact on the user's entry of math. We also describe recognition control techniques, including using user-controlled mappings of allographs to achieve more robust symbol recognition and provide extensions to notation, and UI control of non-spatial information used in recognition. We generally do not discuss the precise user interface implementation necessary to use these techniques, for example whether to use menus or gestures, but just the functionality required. Finally, we provide, in an appendix, a sketch of the recognition and display implementation behind our techniques.