As a woman of a certain age, I often find the subject of retirement drifting through my mind. My friends have the same questions I do. How will we spend our days? Will we have enough money? What about our health? We wonder if life will be stimulating or sapped of meaning. My friends and I are fortunate to have found careers in industries we love and to still have jobs in them. None of us can imagine giving up any of it. And yet.

Editor-at-large Bo Burlingham has also been mulling these questions as he researches a book on the experience of selling a company. Bo notes that "if you look at the literature around business, there's a ton of stuff on starting a company, building a culture, and marketing a product or service, but much, much less on the final phase of people's relationship with their business." Books on exit strategies exist, of course, but they invariably focus on how to get the most money for your company. "There's another side that is just as important, or more important," says Bo, "and that's the emotional side."

For his story in this issue -- "What Am I, If Not My Business?" -- Bo spent time with a group of entrepreneurs who have sold their companies or are weighing doing so. Some of these men and women are at, nearing, or over 65. Others, however, are considerably younger. Bo shows, with his usual insight and sensitivity to his subjects, that there is no minimum age on the emotions stirred up by leaving a company you've nurtured. I recommend his story highly, and not just because it speaks volumes to me.

Our cover story this month explores what we call the Demand Economy -- an economy in which supply is large and demand is small, which pretty much describes the U.S.'s today. For this story, Leigh Buchanan, our other editor-at-large, pinpointed markets of incipient or growing demand, then discovered companies that are poised to serve and profit from them. The health care market, for example, offers tremendous opportunity to smart company builders able to tap into the 71 million Americans who, by the year 2030, will have reached the conventional retirement age of 65 or beyond. (Look for me beyond.) Leigh also delves into the banking, commuting, and insomniac markets, all of them ripe for entrepreneurial magic.

I hope you enjoy these and the other articles in this issue. I look forward to hearing your comments.