For years, hiring managers have wondered whether smooth-talking job seekers could walk the talk. Now, more employers are testing candidates' skills -- before making the hire.

An increasing number of employers are putting candidates for salaried jobs through a battery of mock assignments, stressful "day-in-the-life" job simulations and role-playing exercises. A senior-level candidate might spend a day in an office being bombarded with phone calls, emails and complaints from vendors or subordinates, while a would-be employer judges how well how well the candidate prioritizes and handles pressure. The tryouts supplement interviews, reference checks and written tests.

Hiring managers say the tasks let them see how a candidate performs. The exercises help employers judge a candidate's cultural fit, and "soft" skills like how a prospective manager directs and coaches employees. Advocates say the tests can help applicants, letting them better see whether they would be happy in the job. Some applicants drop out after completing a tryout; those who survive feel validated by the rigorous process.

"Everybody is looking for a crystal ball to predict what a person will actually be like on the job," says Scott Erker, senior vice president of selection solutions at Development Dimensions International, a human-resources consultancy in Bridgeville, Pa., that runs job simulations for companies. "With a job tryout, you're actually seeing a person perform part of the job." The company's clients including auto maker DaimlerChrysler AG and drug maker Sanofi-Aventis SA. Other employers, including the economic-development department in Virginia's Loudoun County government, have created their own tryout tasks.

Employers have long used small-scale tasks to evaluate lower-level hourly workers, such as call-center employees or factory workers. Mr. Erker says there is increasing demand for the tryouts for senior-level, white-collar positions. "There's a realization that executive failure is extremely costly," he says. "Companies want to get all the information they can about the person in order to make a good effective decision."

The tests and tryouts can be time-consuming and expensive -- a full-day exercise can cost thousands of dollars. Some skeptics doubt it is worth the effort and say similar insights could be gleaned from probing interviews and thorough reference checks. Some candidates balk at a tryout -- especially when they are at a senior level and feel their track record should speak for itself.

Employers who use tryouts say benefits outweigh disadvantages. Larry Rosenstrauch, director of the Loudoun County department of economic development, which runs tryouts on its own, says they help him assess whether someone with limited experience will be able to do the job. That is valuable, he says, because he hires people with diverse backgrounds, not just economic-development specialists. One job candidate was sent to meet with a director at a prominent area business and to report back to would-be co-workers at the county-government office. (The business director reported back on the candidate as well; she got the job.)

DaimlerChrysler's Chrysler Group has long asked candidates for hourly manufacturing jobs to perform tryout tasks, such as assembling parts. The company is applying the concept to professional and executive-level hires. During the past year, it has started asking some candidates for plant-manager positions to undergo "day-in-the-life" simulations, in which they juggle a barrage of mock memos and phone calls. Sandra Fiaschetti, a senior human-resources manager, hopes to spread the practice through the salaried ranks this year but says the decisions are left to hiring managers, who have to budget the time and money.

Some managers wonder if it is worthwhile. Gary Kajdasz, a senior manager in product development at DaimlerChrysler, thinks the simulations sound like overkill, at least in his area. He uses an extensive screening test that helps assess how candidates have behaved in past situations, as well as behavioral-interviewing techniques. "From a time standpoint, I think this is probably a good compromise, rather than saying 'OK, you're going to spend one or two days doing some product-development office simulation,' " he says.

But others have embraced it. A Dundee, Mich., plant that makes a joint-venture engine from DaimlerChrysler, Mitsubishi Motors Corp. and Hyundai Motor Co. used four-hour "day-in-the-life" simulations for all of its approximately 50 salaried hires, who include operations managers and plant engineers. In addition to the memo-and-phone bombardment, candidates had to talk with "employees" about a job problem, such as lagging performance, to test the candidates' coaching skills. Bruce Coventry, president of the venture that runs the plant, credits the process with identifying top-caliber, team-oriented employees and helping to keep turnover low.

Greg Schober, an operations manager at the Dundee plant, participated in a simulation when he applied for the job in 2004. He performed an "in-basket" exercise, in which he had to sift through a pile of memos to determine the day's priorities. In the simulation, he saw that the plant was out of a critical component, and the alternate component could be assembled only by certain workers with special training. So he scrambled to revise staffing schedules to allow production to proceed with the alternate part. Later, he coached an "employee."

He found the experience worthwhile. "It's very true to real life in a business environment in manufacturing," he says. "There are things you can't control and you adapt."