Innovation is a funny thing. We'd all like to be innovative, but few of us have "creativity switches" we can turn on at will. (I definitely don't.)

We're a lot better at convergent thinking, providing "correct" answers to relatively standard questions by using knowledge and experience to spot patterns and apply solutions. 

Divergent thinking, coming up with new ideas and new solutions, is a lot more difficult.

And that's okay; there's no reason to reinvent the wheel when perfectly good wheels already exist.

But what if you're trying to do something no one else has done? What if you're trying to serve a market no one else serves? 

"If I'm not qualified to fly an airplane, I shouldn't," says Jim McKelvey, co-founder of Square and author of the great new book The Innovation Stack: Building an Unbeatable Business One Crazy Idea at a Time. "But Wilbur and Orville Wright couldn't be qualified. They couldn't get trained to do something no one had ever done."

"We're so conditioned to have a level of expertise before we begin anything," Jim says. "So when we confront a truly new problem, we disqualify ourselves prematurely... thinking, 'I'm not ready to do this.' Which sounds legit -- but in some cases there's simply no way to be 'ready.'"

In McKelvey's case, the problem was credit cards and small business owners: Expensive equipment, high fees, and complicated infrastructure put taking credit cards out of reach for many small merchants, including those hoping to launch side hustles

So Jim set out to solve that problem, and in the process developed what he calls the innovation stack: Trying to do something new, encountering a series of new problems, creating solutions that lead to more problems... in short, a problem-solution-problem cycle that results in solving an unsolved problem.

But where can you find those unsolved problems that lead to successful businesses?

"The key is to look low," Jim says. "Look at companies that end up taking over entire markets... every one of them looked to the bottom of the market, where people couldn't even participate. If it's financial, people who don't have bank accounts. Automobiles -- look for people who can't afford cars. With airlines, people who ride the bus. Looking past where the market 'ends' is a great way to spot opportunities."

"Everyone already that market," Jim says, "thinks they know where the bottom of the market is, and every communication automatically assumes where the bottom of the market is. That's the assumption you have to fight."

In Jim's case, that led to Square. For Charles Schwab, that led to discount brokerages. For Southwest Airlines, that led to, yep, Southwest Airlines. 

Using the innovation stack to find a way to serve an unserved market can build not just a new business, but a new industry.

Keep in mind The Innovation Stack won't tell you which problems to solve, or even whether the problem you choose to solve is actually solvable.

The only way to prove a problem can be solved is to solve it.

But the book does provide a framework and the tools to help you build your own innovation stack as you work hard to turn your new idea into a reality... and maybe even create a new industry.