Imagine sitting in a cab in New Orleans as the driver pulls out a small device, hooks it up to his phone, and begins raving about how excited he is to be able to take credit cards for the first time. Now, imagine that you are the co-founder of the company that made it possible.

Jim McKelvey is the co-founder of Square, a company that has opened a door for small businesses to take credit cards simply and securely. He’s also the author of a new book called The Innovation Stack in which he shares the core principles by which effective companies develop products that resonate deeply in the marketplace. In this interview, we discuss the founding of Square, that an innovation stack is and why it’s important, and what he’s learned from companies such as Southwest Airlines and IKEA about gaining a footing in a crowded marketplace.

AC Premium subscribers: stick around at the end, where I’ll share my personal takeaways from the interview.