His first major TV role was on the soap opera "General Hospital," where he played Dr. Jeff Webber from 1976 to 1981. After leaving the show, he made guest appearances in various other television series. In 1985 he landed the starring role in "MacGyver," which ran from 1985 to 1992.
Anderson made a number of TV movies in the 1990s, then starred in the sci-fi western TV series "Legend," which only lasted for one season. But he again found success as Colonel Jack O'Neill in the sci-fi show "Stargate SG-1" (a spin-off of the movie Stargate).