Born in Chattanooga, Tennessee. Before pursuing a television career Dennis has worked as a music manager, agent and concert promoter. Among his customers were 'Tom Jones' and Greg Allman. He wrote a guide for actors called "Rating the Agents". On screen he had guest roles in series like Twilight Zone, The (1985) or Magnum, P.I. (1980) and many more. His longest lasting employment is as principal "Mr. Belding" for the teen shows Saved by the Bell, Saved by the Bell: The New Class, and Good Morning, Miss Bliss.