The stereotypical image of the corporate road warrior is an exhausted guy in a wrinkled suit spending too many nights in lonely hotels. But that image is changing, as more travelers find ways to include their families in trips. Nearly half of all travelers expect to bring their spouse on an upcoming business trip, according to a survey by the National Business Travel Association. And according to the Travel Industry Association of America, children tagged along on 32.3 million business trips in 2000, a 250 percent jump from a decade earlier.

For parents, turning business travel into family time is one way to deal with ever-crazier work schedules and limited vacation. And in a slow-recovering economy, it’s a great way to save money. Business functions are often held in swank hotels that families might never go to if they were paying their own way. Since employers generally pick up most of the hotel bills and the employee’s airfare, the marginal cost of bringing the family can be minimal, especially with frequent-flier miles in the bank.

Many companies actually encourage the business-pleasure principle. “Allowing an employee to take a spouse or family member on a trip that has a Saturday-night stay can result in less expense for the corporation than having an employee return on Friday,” says Alison Marble of the National Business Travel Association. Many companies’ in-house travel agents are becoming adept at helping workers find a way to economize by bringing family along. “Our travel department will say, ‘If you spend the weekend, the fare will go down to X’,” says Yukari Finley, a market-research manager for a software firm. “The company likes you to stay.” So Finley, who lives in Amsterdam, will sometimes arrange for her husband, Tim, to meet her on the road. Jackie Bispo, global-travel manager at Jabil Electronics in St. Petersburg, Fla., books traveling executive-and-spouse couples in separate records. That makes it easy to see what the trip would have cost solo, Bispo says, so the employee picks up the difference.

The growth of online travel agencies has fueled the business-pleasure trend, too. Since Web sites like Orbitz, Travelocity and Expedia became popular, business travelers have been seeing the disparity between short-notice business fares and nonrefundable leisure fares. As a result, business travelers are booking trips earlier, which lowers costs and makes it feasible to bring families. In the first quarter of 2003, 54 percent of business-travel airline tickets were nonrefundable, up from 25 percent in 2000, according to a National Business Travel Monitor survey. And as the travel sites beef up customized corporate sections to include company-negotiated discounts, more big firms are allowing employees to book their own travel; that, in turn, makes it simpler to include a partner or kids. Last month McDonald’s signed up Orbitz for Business as its travel provider.

Despite the trend, not all travelers tell bosses they’re bringing the family in tow. And some surely act unethically by padding expense accounts to cover extra costs. But for folks who behave honestly, there’s nothing to feel guilty about, says ethics professor David Messick of Northwestern’s business school. He recommends employees run their bring-the-family travel plans by their accounting department or boss to agree on how to divvy up the costs. “It’s when there’s a reluctance to bring these issues forward that someone thinks there’s something to be hidden,” he says, citing as an example a business trip ginned up to facilitate a family trip to Disneyland. By alerting everyone, he says, “you avoid not only impropriety, but the appearance of impropriety.”

Beyond potential expense-account squabbles, there are other drawbacks to bringing the family along for the ride. Without Little League games to rush home to, many traveling executives put in their most productive workdays on the road. But if a traveler knows her family is expecting to meet her to see “The Producers” at 8, there’s strong temptation to cut meetings short or schedule fewer appointments. Stephen Levin, a technology consultant from San Jose, Calif., and wife Tami, a swimwear designer, both travel frequently for work, and they often meet up on the road. But when Stephen knows Tami’s back at the hotel, “it takes an effort not to be distracted,” he says. His strategy is to overcompensate when Tami joins him. “Sometimes I find myself leaving later than I wanted to so no one questions what I’m doing.”

The Park Hyatt chain is trying to help business travelers keep their focus by adding “kidscierge” services to entertain children. Conventions are going to great lengths to accommodate families. For its San Francisco convention this year, the American Dental Association hired Accent on Children’s Arrangements, a company specializing in providing day care and kids’ activities at conventions. A team of 33 staffers took charge of 170 dentists’ kids, organizing local trips and finger-painting.

For self-employed individuals like dentists, there’s no haggling with the accounting department over expenses, since the costs ultimately come out of the family’s pocket. Yet there are sticky tax issues to navigate when the family goes along on a business trip. Generally, the costs of the trip associated with business–the dentist’s airfare, say–are tax-deductible, as are costs that don’t change by bringing the family along (which include mileage expenses if you drive instead of fly). But additional costs–the second hotel room to make room for the kids–aren’t, says Mark Luscombe, a principal analyst at CCH Inc., a human-resources provider. Restaurant bills should be split fair-and-square, too. Self-employed people must also make sure the business reason for the trip is audit-proof, says Gail Levin Richmond, a tax-law expert at Nova Southeastern University. The IRS has taken steps to facilitate combined business-pleasure trips (last year it announced that it’s fine to use frequent-flier miles earned at work for trips that are purely for fun). Cruise-ship events and long overseas trips, though, still raise red flags. And claiming you attended a convention during your honeymoon is, well, not a great idea. The business-pleasure principle in corporate travel may be gaining hold, but every executive and manager knows it never pays to be greedy.