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In the early '80s, Gary Hirschberg and Samuel Kaymen started selling yogurt to support their struggling farming school. Now their business, based in Londonderry, N.H., is the world's leading organic yogurt manufacturer.

"The idea to sell yogurt came from my business partner, Samuel Kaymen. We had a little nonprofit farming school that was struggling to make ends meet. At every trustee's meeting, while we brainstormed how to keep this thing funded, I would sit and enjoy the most incredible yogurt. Samuel had a small dairy herd and a fabulous yogurt recipe. To this day, we don't know who first said, 'Why don't we just start selling this yogurt?'

"It was an insane idea because neither of us had any relevant business experience. I literally didn't even know what a business plan was at that time. I had been running nonprofits. Samuel had been running an organic farming school and was a dairy farmer. I had a naive view, which in hindsight I'd call a hypothesis, that if we brought the same kind of principles of education, care for the earth, and care for people's health and nutrition that were at play in our respective nonprofits, we could build a brand.

"Samuel had an excellent, world-class recipe for beer and one for pickles. We debated long and hard about which product to market first. Thankfully we came to our senses and realized one segment is difficult enough, and we didn't need to add the burden by trying to be in a number of products.

"Our original venture capitalists were a group of Catholic nuns called the Sisters of Mercy. The dairy industry in New England was on one leg and the sisters saw how our proposal would help struggling dairy farmers come up with new ways to make their farms viable. They loaned us $25,000. We borrowed another $10,000 from the Institute for Community Economics, a socially minded fund based in Greenfield, Mass.

"At first I was unsure about leaving my job consulting businesses on renewable energy topics in China to work on the yogurt business full time.