(FORTUNE Magazine) – IT'S BEEN 40 YEARS since Congress passed Title VII, which banned workplace discrimination based on sex, race, color, or creed, and today scarcely a major company in the land lacks a policy on workplace diversity. So how are we doing? Just so-so. Curious about how its own efforts stack up against other big employers', Enterprise Rent-a-Car recently backed a study by the nonprofit National Urban League. Researchers surveyed more than 5,500 American workers, including managers and CEOs, and the results are thought-provoking. Just 32% of U.S. employees think their companies do a decent job of hiring and promoting people other than white males. Their bosses' view isn't much rosier: Fewer than half of executives (47%) think their own diversity efforts are working, and the majority (59%) say it's partly their fault for not being involved enough. (To see the full study, "Diversity Practices That Work: The American Worker Speaks," go to www.nul.org.)

Happily, the study is short on hand-wringing and long on analysis. The researchers singled out eight companies in which diversity is more than just a buzzword and describe specifically what they're doing. (Four of the exemplars--PepsiCo, UPS, Pitney Bowes, and Procter & Gamble--also made FORTUNE's list of the Best Companies for Minorities, at www.fortune.com/diversity.) One thing is clear: There is no one-size-fits-all formula. While the successful companies stress diversity training for managers, the similarity in their approaches ends there. Many, for instance, sponsor "affinity groups"--in-house organizations for women, African Americans, and Hispanics--to give members a sense of solidarity and mutual support. UPS, though, doesn't have them. "We don't want to accentuate differences among us," says Lea Soupata, senior VP of human resources. "We're all part of the same team." Nor does UPS have plans to hire a diversity officer. "It's not just one person's job; it's everybody's job," Soupata says. Evidently. A striking 58% of its senior managers are female, minority, or both.

Meanwhile, to get a broad mix among the 6,500 management-track employees it hires annually, Enterprise Rent-a-Car dispatches diverse teams of recruiters: male, female, black, white, Asian, even (here's a shock) people over age 40. Ditto for the actors in its TV commercials. Enterprise also rewards managers for hiring and developing people who reflect local markets. Since its branches are mostly in neighborhoods (only 150 of 5,700 are at airports), staffing in, say, San Francisco differs markedly from that in San Antonio or St. Louis. "We want people who speak the same language, literally and figuratively, as our customers," says Ed Adams, VP of human resources. "We don't set quotas. We say, 'Reflect your local market.'" None of that is exactly hurting business, Enterprise executives say. Revenues jumped fourfold, to $7.4 billion, in the past decade; it's now the industry leader.

Moreover, the Urban League study shows that at the eight companies where diversity is a fact of life, productivity growth in the past four years exceeded that of the economy as a whole by 18%. "Getting serious about workforce diversity isn't just the right thing to do," notes League president Marc Morial. "It's the smart thing to do." Seems so.