(FORTUNE Magazine) – Dear Annie: I work for a company that has very few (almost no) women at or near the top ranks of management. Should I speak up about it, or just keep quiet? My concern is that anything I say will seem self-serving, since I am a woman myself. Any thoughts? --Knocking on the Glass Ceiling

Dear KGC: "There's safety in numbers," says Lois Frankel, Ph.D., president of Corporate Coaching International (www.corporatecoachingintl.com) and author of a new book, Nice Girls Don't Get the Corner Office (Warner Books, $19.95). "Why not get together with other women in the company to discuss the issue? If you can make a strong business case for more diversity at the top, senior management will be more inclined to listen to you and not dismiss you as a bunch of whiners."

Once you've diagnosed how your company is failing to capitalize on the opportunities diversity presents, and come up with some specific, cost-effective suggestions for remedying that, Frankel suggests putting it all into a succinct PowerPoint presentation that emphasizes the dollars and cents involved. You might throw in a few words about a recent study by Catalyst (www.catalystwomen.org), which shows that among 353 U.S. companies, those with the most women at the top reported return on equity 35% higher, and total return to shareholders 34% higher, than those with the fewest women. The researchers are careful to note that a correlation doesn't necessarily imply causation, but who knows?

Send questions to askannie@fortunemail.com. Annie offers advice weekly at www.askannie.com.