A. Yes. In fact, 16 percent of American companies have formal unpaid sabbatical programs, and 5 percent offer paid sabbaticals, according to the Society for Human Resource Management. Corporate sabbaticals are usually shorter than academic ones, said Elaine Varelas, managing partner of business development at Keystone Partners, a talent management firm in Boston. "Unlike the academic world, in the business world it's out of sight, out of mind," she said. "The longer you're out of touch, the higher the risk that you will seem less important in your job than you are." Ms. Varelas suggested taking no more than three months off. Don't consider asking for a sabbatical unless you are a high-performing employee who has been at the company for several years. If you are an average or marginal performer, you risk being perceived as someone who isn't serious about his or her career, she said.

A. If you're burned out you should take a vacation, not a sabbatical. The best case for a sabbatical is a business case, not a personal one. Write a proposal outlining how both you and the company will benefit from your time away, what you intend to do and what you hope to achieve, said Melanie Holmes, a vice president at Manpower, the staffing firm in Milwaukee. If you want to take a continuing education class, for example, or volunteer to work in Africa on a project to fight AIDS, describe how your efforts will relate to your professional development goals. "Include information about how you will be a better employee, that you will come back refreshed and more creative," Ms. Holmes said. You may also be able to use the current economic downturn to your advantage. If your company is looking for ways to cut costs, this could be a good time to win approval for some unpaid leave, she said. You will also need a plan for covering your responsibilities, one that shows how your work will be seamlessly handled by others while you are away, so that neither clients nor co-workers suffer, said Rachelle J. Canter, president of RJC Associates, a leadership development firm in San Francisco and author of "Make the Right Career Move" (Jossey-Bass). "Be specific," she said. "Tell your boss, 'Here is what I will do, this is who will cover these tasks, and I have set up lunches with these three clients to ensure a seamless handoff.' You don't want your boss to have to figure out how he can do this for you, because then it's just one more thing on his plate."

A. If you don't, you're likely to waste it, said Rich Gee, an executive coach in Stamford, Conn., who took a one-month sabbatical four years ago when he was a product manager at Gartner Inc., the technology research firm. Mr. Gee had a number of goals: to take a class, to read several business books, to spend some time with family and to evaluate his career. "But I didn't plan it effectively and didn't get much accomplished," he said. "You need to block out time for each activity every day, because you need structure and a time management system in order to get anything done."

A. They usually engage in activities that benefit them professionally, said Stefanie Smith, president of Stratex, an executive consulting firm in New York City. That doesn't mean you have to enroll in an executive education program — although you could. But whatever you do, there needs to be a professional gain. "Even if you spent your sabbatical rock climbing, you had the experience of successfully tackling a challenge, and that translates to changes in leadership style and self-perception," Ms. Smith said.

A. The worst that will happen is your boss will see that you aren't indispensable, but if you're doing your job right, you shouldn't be indispensable anyway, Mr. Gee said.

A. As soon as possible, have a lunch with co-workers to talk about what you did on your sabbatical, what you learned and how it will let you contribute more to the team, Ms. Smith said. That will help engender camaraderie rather than resentment. "Come back to the office with one to three professional development goals and be prepared to articulate how those goals will also benefit the department and the company," she said. But don't gush about the singing lessons you took, or how you learned to play guitar. "Keep that stuff to yourself," she said.

E-mail: ccouch@nytimes.com.

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