This document discusses strategy prototyping as an approach for developing strategy in uncertain times. It notes that traditional strategy development is slow and done behind closed doors, but that organizations now realize agile principles can be applied to strategy as well. Strategy prototyping involves taking small, iterative steps through hypothesis testing, prototyping concepts, and getting user validation rather than spending a long time planning. It advocates acting into the desired future rather than thinking one's way into it. The document provides an example exercise where participants take on roles to reframe a client's brief and identify concepts and metrics to measure learning for an online dating site client.