Business: Cockney Savvy

Since Led Zeppelin went aloft in 1968, the British rock has sold more albums than the Rolling Stones, played to bigger audiences than the Beatles in their heyday, and brought Atlantic Records $50 million in business. Much of that success is due to Zeppelin Manager Peter Grant, 39, a burly cockney blend of street smartness and business savvy.

A onetime sheet-metal worker, Grant scurried into British show business as a bit-actor, professional wrestler (under the name Prince Massimo) and rock-group errand boy before becoming manager of the Yardbirds in 1967. When the Yardbirds disbanded...