(FORTUNE Magazine) – Dear Annie: I've been in a middle-management job with a FORTUNE 500 company since mid-2000. My evaluations have been excellent, my team has accomplished great things, and I get along extremely well with my boss. The thing is, I have a couple of friends at other companies who keep telling me that it's risky to stay too long at this level, and that if I don't get promoted into senior management soon, I should start looking elsewhere. I'm inclined to stay put and wait it out. Who is right? -- Organization Man

Dear OM: Your friends may be on to something. A new study by Management Recruiters International in which researchers polled 200 human resources chiefs across the U.S. found that before stepping up to a senior position, most people stay in middle management for 6.3 years on average. "By the sixth year at the middle-management level, most companies have already decided whether a manager has senior-level potential or has become a 'career middle manager,' " the study says, adding that if someone hasn't attained senior status by a few months into year seven, his chances of ever doing so are "significantly reduced." The authors are at pains to point out that getting stuck in the middle isn't necessarily a disaster, since the HR folks polled claimed to regard career middle managers as "critical to the success of the company." Still, if your goal is to reach the executive suite one day, you may not have much longer to wow the powers that be.

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