(FORTUNE Magazine) – Dear Annie: I worked for a company for three years very successfully, with excellent performance reviews, substantial raises, and big bonuses. But two weeks after my last glowing review, my boss left a message on my home answering machine saying, "We need to go our separate ways." I requested in writing a reason for being fired, but the company replied it didn't need a reason. It's also let several others go without saying why. What do I tell prospective employers? I've already had one interview where the hiring manager didn't believe I don't know why I was fired. --Mystified in Massachusetts

Dear Mystified: Says Barbara Herzog, a Washington, D.C., career consultant: "It may be a case of hidden downsizing. Sometimes companies don't want to announce that they are cutting staff, out of concern about adverse effects on their stock price or market position. So managers clam up and pick people off one by one." Herzog hopes you kept copies of your rave performance reviews (and recommends, by the way, that everyone do the same). If so, here's what you can tell interviewers: "My previous employer didn't reveal the reason for my termination. In view of my excellent record at the company, I surmise I was part of an unannounced, close-to-the-vest downsizing. A number of others were let go without explanation too. I'd be happy to share with you my record of bonuses and outstanding performance reviews for the past several years. Would that help?"

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