If you want to truly understand a topic, design a game for it. This chapter provides a framework for running your own ‘game jam’ — or, if you only have a small chunk of time — a game design challenge. A game jam is a game design tradition to gather a range of prospective game designers that work in groups to make a fully– functional game, from idea to iteration, within a set amount of time. The advantage of community– based design models like this one not only builds creative collaboration, but also allows for playtesting and natural enthusiasm around game design. It reminds all designers, no matter how accomplished, that an idea is only as good as its execution, and that productivity is measured in moments, not months.