There are only two times in a workday that matter, say the authors: PN, prior to a nap, and AN, after a nap. Most businesses offer lunch breaks and coffee breaks, they note, but few offer nap breaks. Yet sleep-deprived workers are less productive and more apt to make mistakes.

In a workplace survey, posted at www.napping.com, the Anthonys discovered many secret nappers in the nation's workplaces. Some people resort to napping in bathroom stalls or in their cars in the company parking lot. A female musician, who is either a small person, or plays a cello, reported she napped in her instrument case.

Workplace napping as a fatigue management strategy has been the focus of a number of studies in the transportation industry. Researchers found in the early 1990s, for example, that pilots who napped in the cockpit for forty minutes during the cruise portion of transoceanic flights were more alert for the remainder of the flight than non-napping pilots. The FAA, however, has yet to authorize napping in the cockpit. Since 1998, the Union Pacific railroad has allowed one crew member at a time to nap up to 45 minutes as long as the train is stopped, secure, and safe.

A small number of companies now offers nap rooms. At others, being caught napping on the job still constitutes grounds for dismissal. Camille Anthony, a fiscal consultant, and Bill Anthony, a psychology professor at Boston University, would like to see such attitudes change. The absence of couches and overly bright lights, they assert, won't make tired workers more productive. It just makes them more tired. Some managers might find that message a powerful wake-up call.