Became a musician at age nine (date approximate)

Continued to play guitar and bass

Acting debut as an understudy to brother Keith who appeared with their father in "Tobacco Road"

Made stage debut when he replaced brother Keith at age 16 in "Tobacco Road" (date approximate)

Made TV Debut in "Bonanza"

Feature acting debut, "The Cowboys", starring John Wayne

Co-starred with father John in second episode of brother David's "Kung Fu"

Had bit part in Martin Scorsese's "Mean Streets"

TV series debut as a regular on the ABC series adaptation of "The Cowboys"

First starring role as Johnny Chrystal in "The Pom Pom Girls'"

Had supporting role in "Coming Home"

Starred in the L.A. production of William H. Hoffman's play, "As Is"

Worked as a driver of Corvettes for Mobil Oil and B F Goodrich

Raced Ferraris with Paul Newman at Daytona and Sebring

Narrated and starred in Samuel Fuller's WWII drama "The Big Red One"

Appeared with brothers David and Keith as the outlaw Younger brothers in Walter Hill's "The Long Riders"

Played Robert Cohn in NBC remake of "The Sun Also Rises"

Had most famous feature film role as Lewis, the positive-thinking leader of "Revenge of the Nerds"

Sang onscreen in "Number One with a Bullet"

Starred in "As Is" for Broadway on Showtime

Reprised role of Lewis in "Revenge of the Nerds II"

Had cameo as himself in Robert Altman's "The Player"

Played Lewis a third time in the Fox TV-movie sequel "Revenge of the Nerds III: The Next Generation"; also co-produced

Co-produced the TV-movie sequel "Revenge of the Nerds IV: Nerds in Love"; also starred

Reunited with "Nerds" castmate Anthony Edwards in an episode of "ER" (NBC)

Played a Skinhead in "John Carpenter's Escape From L.A."

Played the father in "Max Keeble's Big Move"

Cast as Lizzie's father in the series, "Lizzie McGuire" (Disney)

Directed an episode of "Lizzie McGuire" titled Lizzie's Eleven

Reprised role as Lizzie's father in "The Lizzie McGuire Movie"

Co-starred with Michael Madsen in the independent horror/thriller, "Hoboken Hollow"