Koenig wrote episodes of the animated "Trek" series (1973)--although he did not appear as Chekov on the series-- and the Saturday morning live-action fantasy series "Land of the Lost" (NBC, 1974-1977), as well as the short-lived primetime series "Family" (ABC, 1976-1980) and "The Powers of Matthew Star" (CBS, 1982-1983). The actor lectured regularly in psychology at a number of California colleges, toured extensively in stage productions--including several with "Trek" veteran Mark Lenard--appeared in several B films and telepics, and enjoyed a lengthy side career as a popular acting and directing teacher.
Throughout the ups and downs that went with being a "Trek" actor--including public animosity with the franchise's leading men--Koeing continued playing the role which made him famous on the six popular "Star Trek" movies from 1979-1991 (he was used to particularly strong effect in "The Wrath of Khan" and "The Voyage Home"), and helped pass the baton to the "Next Generation" featuring Picard and crew with a cameo in the 1994 crossover "Star Trek: Generations." He also had a recurring role, villainous Alfred Bester (named after the popular sci-fi novelist), on the syndicated sci-fi series "Babylon 5" from 1994 to 1998.
In print, Koenig was the first of the "Trek" crew to pen a memoir of his time on the series, Chekov's Enterprise, in 1980, as well as the 1998 follow-up Warped Factors: A Neurotic's Guide to the Universe. He also authored the satirical novel Buck Alice and the Actor-Robot and he has written several comic books. Koenig is the father of actor Andrew Koenig, who spent several seasons as Kirk Cameron's sidekick Boner on the ABC sit-com "Growing Pains."