Waggoner was an announcer and performer on The Carol Burnett Show from 1967 to 1974 and played Steve Trevor in The New Adventures of Wonder Woman from 1975 to 1979. He was the first centerfold for Playgirl (albeit no frontal nudity) in June 1973. Prior to joining Carol Burnett, Waggoner was a finalist for the title role in the TV series version of Batman. He has appeared on a few, but not all, of the Burnett Show reunions on television. Waggoner left the Burnett show, feeling his contribution was undervalued and in hopes of pursuing a starring career. His spot on the show was filled by frequent guest star Tim Conway who was used more frequently in the programs' skits. He appeared in several TV movies and minor motion pictures during the 1970's and 1980's, often cast for "hunk" appeal and has made guest appearances on numerous television series including Charlie's Angels, Mork and Mindy, The Love Boat, Golden Girls, and Ellen.

In 1979, Waggoner founded Star Waggons, a company that leases customized trailers for use by the entertainment industry; it is the largest such supplier and brings in USD $20,000,000 annually.

Waggoner retired from full-time acting to run the company, but still makes occasional appearances, often parodying his earlier image (That 70s Show, Return to the Batcave).