Voice coaches say a growing number of their clients are professionals who want to improve their delivery to help their careers. "I've trained doctors. I've trained CEOs. I've even trained one of the contestants on Top Chef," says Bettye Zoller, a Dallas-based coach. "A great voice makes you sound more interesting, more intelligent and more trustworthy." The American Speech-Language-Hearing Association, founded to help disabled people, says about 1,000 of its members now help the able-bodied "style" their voices.