He is best known for his work on the Star Trek franchise from 1987 to 2002, having worked on four Star Trek shows: The Next Generation, Deep Space Nine, Voyager and Enterprise.
By 1976 he was serving as assistant director, on the film Leadbelly, starring Madge Sinclair and Albert Hall, and as first assistant director on the television series Dynasty and T.J. Hooker.
He has also directed episodes for such television series as Beverly Hills, 90210, seaQuest DSV, Lois & Clark: The New Adventures of Superman, M.A.N.T.I.S., Sliders, JAG, and Dark Angel.
Actor Garret Wang recalled Les Landau directing the Voyager episode "The Chute".
Wang said that while he tried to focus on his part, the series' other actors often engaged Landau about possible directing opportunities.