Kevin P. Ryan's encore to DoubleClick—the ad-serving behemoth he sold for $1.1 billion to private equity firm Hellman & Friedman in 2005—is AlleyCorp, a variety pack of Internet start-ups he founded in New York City. His hottest business is Gilt Groupe, a site for bargain-priced luxury brands, which he expects will employ 500 people this year. The other businesses are 10Gen (data storage), Music Nation (a community for performers and fans), ShopWiki (a shopping search engine), and the Business Insider (a widely read business news site). As chairman of two companies, a board member for several for-profits and nonprofits, and the father of three, Ryan says there's one thing he won't delegate: bringing on people to whom he can delegate.

I used to think business was 50 percent having the right people. Now I think it's 80 percent. The best way to be productive is to have a great team. So I spend more time than most CEOs on human resources. That's 20 percent of my week.

I interview a potential employee literally every day, for about an hour. Gilt, the company that currently occupies me most, hired 300 people last year, and I interviewed 50 of those—plus all the candidates we didn't hire. I heavily overinvest in recruiting. I have an understanding with certain search firms that if you find someone great, don't wait until there's a job opening—send him to me. We typically have eight full-time recruiters in-house. The technology group meets weekly to discuss recruiting, and I try to be at at least half those meetings. At one recent meeting, I found out that someone had taken the open-position listing off our website because we had filled all our senior-engineer jobs. I said, That's crazy. You keep that up there all the time, because we always have room for an incredible engineer. I never want to think, OK, we have our team. Instead I think, If we have 10 engineers or 10 directors, one of those is No. 10. Is there someone out in the market who is much better than our 10th person? The answer is generally yes.

I sit down with the HR director every two days. We talk about recruiting and other issues. For example, I'm trying to get rid of some of our policies, like Net-flix has done with its vacation policies—they've said, Take whatever you need, so long as you get your work done. I want to do things like that, too. And I want to keep on top of what's happening with the managers, because I don't want the good people under them leaving. People will put up with a lot if they like their manager, but they'll leave if they don't.

I don't have an office. I sit in a cubicle with everybody else. That's partly so no one can ask for an office, which in a fast-growing company isn't practical. But it's also so I can keep my finger on the pulse of how people are feeling.

I carry a little notebook with the names of 35 or 40 people in the company, and every week I look at it to make sure I'm in touch with everyone. The top eight or 10 people I'm going to see automatically. But there are always 20 or 30 people who are up-and-comers or one or two levels down, and I want them to know I'm paying attention. So I'll run down the list and notice I haven't talked to Mary in a long time and send her an e-mail, even if it's just to say, Great work. Once a quarter, I go through my list of contacts—a couple of thousand of them—to see if there's anyone I should be reaching out to about a job. Our head of business development is a guy I interviewed at DoubleClick. We didn't end up hiring him, because there was someone with slightly more relevant experience. But I kept in touch with him for 10 years, and now he's here. Every event I go to or panel I sit on does double duty, because I'm also using the opportunity to scout for talent.

Intensive as all this is, I ultimately save time, because I can delegate with confidence. I don't feel compelled to have weekly one-on-one meetings with senior managers. We'll meet once a month, but otherwise, I just ask them to send me an e-mail with a few paragraphs about whatever they think I should know. I'm also comfortable being away from the office more often. I take six or seven weeks of vacation a year, though I'm always connected. When you've got the best people running things, you can take your kids skiing in France.