I was delighted to read Steve Blank’s great post featuring the work of my friend and colleague Marc Gruber. Marc and I have been colleagues since my days in the entrepreneurship program at Wharton and he continues with his research and teaching in this area at EPFL. Steve has recently discovered Marc’s 2017 book Where To Play which uses vast academic research and plenty of practical examples to help identify promising initial markets for a new offering. Steve calls it an important addition to the “Lean Startup” toolkit. For people who follow my work, it’s a nice way to begin to understand the whole concept of competitive arenas.