This book started all “Lean Startup” movement. Eric Ries picked up the “Lean” methodology implemented by Manufacturing, repackaged it and made it the way of life for startups. This book talks about how customers should be included in the product development right from the beginning and should validate your product at every step. It mentions how a startup is just a series of experiments in which you validate or invalidate your assumptions. Every person who wants to start a startup should read this.