One Entrepreneur, Three Radically Different Companies: Here's How She Did It As the co-founder of Cisco and Urban Decay, Sandy Lerner has made an impact in the worlds of technology and cosmetics, and now she is working to change the country's food production infrastructure through organic and sustainable farming.

It just goes to show that you never know where your passions will lead you. Sandy Lerner has found success in three completely different industries over the course of her career. She co-founded tech giant Cisco Systems and then went on to co-found the much beloved cosmetics brand Urban Decay. Lerner is also an author and philanthropist, and is the Chairman of Chawton House Library, a research and writing center housed in a restored estate that belonged to Jane Austen's family in Hampshire, England.

Her advocacy for animal welfare is a driving force behind Lerner's most recent venture, an organic, sustainable farm in Upperville, Virg. called Ayreshire Farm. We caught up with Lerner to talk about making big changes by starting in your local community and grabbing your window of opportunity.

Q: Knowing what you know now, what would you have done differently when you were first starting out?

A: I think I was like 99.9 percent of other Americans, and I was absolutely naïve about how controlled our food system is by the [food] packer and producer cartels. I thought our biggest problem was generating good economic models for sustainable organic farming…but I wasn't even close. I thought I could provide a good model to enter sustainable farming and recreate our traditional food system, but unfortunately that had little to do with the reality of producing food in this country today.

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Q: What do you think sets Ayrshire Farm apart?

A: We tick all the boxes: It really is organic and humane. We do have endangered Heritage breeds and we are raising them in a natural way. There are a lot of people who want to walk the walk and talk the talk, but when you scratch underneath the surface, they are maybe doing one [of those things] and not even that much. We've added a lot to the national organic program in terms of various husbandry issues. I also think we've got some of the best food in the country, and it really is okay to eat it. It's the real thing.

Q: How has your previous experience informed how you run the farm now?

A: I grew up on a farm and my grandfather raised animals organically, and I think that shaped how I think things ought to be. I didn't know about factory farming until I was in college. I certainly didn't have any delusion that I was going to solve the problems in the food system for the whole country, but I can make a local difference.

I had very simplistic view that if we did things the way my grandfather did them, this would be easy. But a lot of things have changed. I didn't realize that step zero wouldn't be getting a farm and getting the animals -- step zero would be to rebuild our food infrastructure. It's kind of like trying to put out a forest fire with a damp washcloth. Once you tamp it down someplace it springs up somewhere else.

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Q: So would you say that you're glad you didn't know about this beforehand?

A: You know I've been in three businesses, and I can tell you absolutely in all three cases, that it's better not to know [laughter]. You'd never get out from under the bed.

Q: What is your best advice for aspiring entrepreneurs?

A: I think there's a lot of misinformation about entrepreneurs – I like the term small business person. When I was at Cisco I liked to be called an industrialist. I think, if you're passionate, great, but it doesn't pay the bills.

My advice would be to first make sure there's a market there. And the second thing I see people doing is doing the opposite, grinding this business plan, trying to figure out everything you can, to the point that the market and the opportunity passes them by. I think at some point you have to believe in your own research and satisfy yourself that there's a market there. You just have to do it. You can get stuck in a morass trying to know everything.

I come from a long line of small business people, and you have to go into this understanding that running a business for yourself is not necessarily a family-friendly endeavor, and you really need to be prepared to do this long after it's lost its caché. You will still be in business and have a whole bunch of people, if you're lucky, depending on you. If you decide to stop or get off, this [business] has a life of its own, and it will involve parts of your life that you never even thought about.

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This interview was edited for clarity and brevity.