Willy Wonka may never have subjected the Oompa Loompas to personality tests, but the tactic has proved invaluable to David Taiclet and his real-life chocolate factory. Along with his co-founder, Taz Murray, Taiclet sat down in 2002 to craft a strategy for making Alpine Confections, based in Alpine, Utah, one of the largest candy makers in North America. To help chart a course of action, they turned to the Test of Attentional and Interpersonal Style, or TAIS, and learned that their management team may have been slow to act because it was stacked with more thinkers than doers.

Working with a consultant, Taiclet and Murray used the results to prioritize more effectively, and the result has been two major acquisitions in the past two years and a major licensing agreement with Hallmark. "The test illuminated some of our management tendencies," Taiclet says, "and our confidence level definitely increased as a result."

While psychological tests have long been a part of the hiring process for many companies, a growing number of CEOs are using these multiple-choice mind games to help them better manage employees already on the payroll. According to the Association of Test Publishers, overall employment testing, including personality tests, has been growing at a rate of 10% to 15% in each of the past three years.

Alpine's personal Nostradamus is a former Inc. 500 CEO named Keith McFarland, who founded McFarland Strategy Partners four years ago and uses the TAIS to help companies cultivate talent within their ranks. "The best way to grow a business is to grow the people," McFarland says. "It just doesn't make sense to be replacing people all the time." An entrepreneurial company's dynamic changes dramatically within its first few years, he says, and all too often the management team does not evolve together. Testing helps bridge some of the gaps.

When working with a company, McFarland administers the 144-question TAIS, reviews the computerized findings with employees individually, then embarks on a "strategy slam" -- essentially locking senior staff in a room for 48 hours and brainstorming. Test takers might learn that they have high "external distractibility" or easily express support and affection, and these qualities are reconciled with those of their colleagues. The goal is three-pronged: fostering self-improvement, helping employees understand one another by sharing their test results, and giving the CEO insight into his or her team.

The TAIS was first developed for, and is still used by, Olympic teams and elite military units -- small groups in high-pressure environments with one common goal. Sound familiar? Over the years, it became clear that challenges on the track or the battlefield weren't all that dissimilar to those in the boardroom, and business leaders have since adopted the test as their own. The questions involve topics you would expect (personal decision-making style) and slightly more obscure predictors of business behavior (high school dating patterns). McFarland acknowledges that other tests offer their own insights, but he was drawn to TAIS because it focuses on action and performance.

"The best way to grow a business is to grow the people. It just doesn't make sense to be replacing people all the time."

That said, there is no shortage of other tests with ardent advocates. David Duncan, chief operating officer of Silver Oak Cellars in Oakville, Calif., turned to the Birkman test to help his staff learn about him as much as he sought to learn about them. When Duncan took the reins of his family's 85-employee winery a year ago, he inherited a management team that had close to a decade of experience in grapes. In hopes of writing a new chapter in the company's history, Duncan had the group take the Birkman, which measures 11 components of behavior, highlighting everything from morning grumpiness to whether people are "outdoorsy." Perhaps even more telling than the test is the off-site retreat that typically follows, where employees come together as a group and attempt to explain, well, themselves. "It led to a real breakthrough of everyone's likes and dislikes, as opposed to their skills," Duncan says. "Those little insights are the key to a functional team."

Duncan is quick to concede that the Birkman is not a magic solution for all woes, but the healthy dialogue that comes during a Birkman retreat lays the foundation for working relationships that he believes can have a tangible effect on the bottom line -- especially in a fast-changing, fast-growing entrepreneurial company. "If I understand you and you understand me," he says, "a lot of those business processes fall into place."

Ginny Corsi, an executive consultant with Strategic Solutions International in Boulder, Colo., says her clients are often stunned that the Birkman's seemingly benign questions -- such as how much time you prefer to spend alone -- can create such accurate personality sketches. "What the Birkman says is that there is absolutely no normal behavior," she says. "Nobody's scores are better than anybody else's. It just says, 'Here you are.' The beauty is that you learn about yourself through this profile." Entrepreneurs tend to enlist the help of friends when launching a company, and the result is often a homogeneous staff, at least on the surface. The Birkman identifies key differences, and can suggest who might be more effective -- and happier -- as, say, a sales manager versus a CFO.

Michael D. Griffin, the CEO of New York City-based Money-Media, who uses the Birkman to build relationships within his 50-employee financial publishing company, agrees. Griffin's own evaluation found that he seeks to develop consensus, but coupled with a high level of energy and drive, he also tends to make decisions quickly. Those findings were valuable personally, but he also found that the information gave his staff greater insight into his rationale, allowing them to understand, if not adapt. "What appeals to me is that the test tends to frame everything in a positive sense rather than as some sort of flaw that you have to overcome," he says. "All of us in this world are different, and we're going to approach things in a different way. A lot of times, there is no right way."

With almost any of these evaluations, the true value comes from the review period, which typically brings staffs together. It's not quite sitting around the campfire and singing "Kumbaya," but test makers and test takers alike say that simply sharing a common, and quite often, emotional, experience yields results.

The 180-question Caliper test, with users ranging from FedEx to the Chicago Cubs, has been used for decades as a hiring tool, lending some objectivity to an inherently subjective process. But these days, Caliper, based in Princeton, N.J., takes as much as half its business from companies looking to use the test for on-the-job management. That number has grown in part because of the economic downturn. "Companies need to increase the productivity of existing people," says Caliper CEO Herb Greenberg, who created the test in 1961 and estimates more than 28,000 companies worldwide have used it. "It's not so much what employees are doing. It's what they might do more."

Anne Mariucci spent 20 years in corporate America before purchasing a minority stake in the WNBA's Phoenix Mercury last year. Having used the Caliper "extensively" in her former life and remembering the sting of hires gone wrong when she did not, the test was something she immediately wanted to bring to the hardwood. All three of the team's new coaches were vetted, in part, by using the Caliper, and she plans to use the test for evaluating potential draft picks. But perhaps more importantly, Mariucci says, the results give her a framework for running the organization during the crunch of the season. "If a person isn't dotting the I's and crossing the T's, we know why, and we can surround that person with people who complement that and pay attention to detail," she says.

But before you dole out the No. 2 pencils, there are a few caveats. The first consideration is cost. A typical Caliper test and profile runs $265 per person, and the more detailed consultations, such as McFarland's TAIS, can cost thousands. A growing company may prefer to spend its money on something more concrete. The testers counter that such an investment is even more essential for a start-up, where one or two wayward personnel moves can deal a devastating blow. "When Microsoft makes a decision, it's not nearly as critical as a decision for XYZ Computer Corp. that's fighting its way up," Greenberg says. "For the start-up company that isn't bathed in money, these decisions are often life and death."

The other concern is effectiveness. While such companies tend to be loyal to their soothsayers, entrepreneurs are by nature a defiant, know-it-all bunch, and there are plenty out there who may prefer their BS detectors to the Birkman. "I think a lot of managers do it intuitively," McFarland says. "And I don't want to take anything away from the greatest computer ever made, and that's the human brain."

Tests can be a valuable resource for CEOs, says Benjamin Dattner, an adjunct professor of psychology at New York University and the president of Dattner Consulting, but he cautions against reading too much into them. They may provide a window into an employee's personality, he says, but they do not necessarily examine situational factors, such as a company's structure, that might be the root of the problem. "Situations are strong influencers of personality," he says. "I do find that there is an overreliance on the tests. They're simple and don't always examine the ambiguity of the team dynamic."

Of course, choosing a test can be a challenge in itself. Even the testers agree, there is no right answer. The best first step is to identify potential areas of improvement within your company and determine what role your staff's personalities might be playing, for better or for worse. If performance and execution are problems, then the TAIS may be your best option. If the concerns are more abstract and you want to foster a better working dynamic among managers, a test such as the Birkman might be more appropriate. The Myers-Briggs and the DISC are among the other tests that have developed followings.

Then again, there's no reason you can't mix and match. Aaron Kennedy, founder of Noodles & Co., based in Boulder, Colo., uses both the Caliper and Birkman to help maintain his original, customer-driven culture now that he presides over close to 90 locations and a growing franchise operation. "Instead of using one uniform management and communication style, I'm able to customize my approach with each of the people on the team," he says. "If we could've afforded it and I had known about it, we would've done this earlier."