At first glance, it seems like a pretty basic question. But there’s a multi-billion-dollar industry behind it. Just search the word “leadership” on Amazon.com—you’ll get a list of 69,000+ books to choose from. The amount of literature and different (often conflicting) points of view out there is staggering.

That’s why I had to pause when Simon Mainwaring asked me for my definition. Simon is one of Fast Company‘s “expert bloggers” and author of the New York Times‘ Best Seller We First. (If you haven’t picked it up already, I recommend you do so. It’s a smart look at the new social marketplace and how we can use social media to be a force for good in the world.)

I interviewed Simon for an upcoming conversation on Let Go & Lead. But before he finished the conversation, he turned the camera back on me to get my point of view. If you’re interested, you can check out the full interview on Fast Company by clicking here.

Back to his question: what’s my definition of a leader? Well, I think in its most fundamental sense, a leader is anyone who has followers. Leadership is defined by the authority that others entrust in and bestow upon us. So in my mind, it comes from a place of service, rather than a place of command and control.

I’d love to hear what you all think. What’s your definition of a leader?