Is your "big idea" worth pursuing? What if you could test your business model earlier in the process--before you've expended valuable time and resources?   You've talked to customers. You've identified problems that need solving, and maybe even built a minimum viable product. But now there's a second bridge to cross. How do you tell whether your idea represents a viable business? Do you really have to go through the whole cycle of development, failure, iteration, tweak, repeat?   Scaling Lean offers an invaluable blueprint for mod­eling startup success. You'll learn the essential metrics that measure the output of a working business model, give you the pulse of your company, communicate its health to investors, and enable you to make precise interventions when things go wrong. You'll also learn how to:   · ballpark the viability of a business model using a simple five-minute back-of-the-envelope estimation. · stop using current revenue as a measure of progress (it forces you to fly blind and, often, to overpromise to your shareholders) and instead embrace the met­ric of traction--which helps you identify the leading indicators for future business model growth. · set progressive goals that set you up for exponen­tial long-term success by implementing a staged 10X rollout strategy, like one employed by Face­book and Tesla. · stop burying your breakthrough insights in failed experiments, but rather illuminate them using two-week LEAN sprints to quickly source, rank, and test ideas.   Ash Maurya, a serial entrepreneur and author of the startup cult classic Running Lean, pairs real-world examples of startups like Airbnb and Hubspot with techniques from the manufacturing world in this tacti­cal handbook for scaling with maximum efficiency and efficacy. This is vital reading for any startup founder graduating from the incubator stage.