Has appeared in episodes of three different series with Garwin Sanford: MacGyver (1985), Stargate SG-1 (1997) and Stargate: Atlantis (2004).
He has appeared in episodes of three different series set in Colorado, USA: Legend (1995), Stargate SG-1 (1997) and Stargate: Atlantis (2004).
He was considered for the part of John McClane in Die Hard (1988).
Played his most famous character, Angus MacGyver, a total of 142 times: in all 139 episodes of MacGyver (1985) and in two TV-movies, MacGyver: Lost Treasure of Atlantis (1994) and MacGyver: Trail to Doomsday (1994). The only characters he has played more times are Dr. Jeff Webber in General Hospital (1963) and Colonel/Brigadier General Jack O'Neill in Stargate SG-1 (1997). He briefly reprised the role in a 2006 Superbowl TV ad for Mastercard.
From the time he first appeared on television in 1976 until his "retirement" in 2005, he was a regular on one series or another every year except for 1984, 1993, 1994 and 1996: General Hospital (1963) from 1976 to 1981, Seven Brides for Seven Brothers (1982) in 1982, Emerald Point N.A.S. (1983) in 1983, MacGyver (1985) from 1985 to 1992, Legend (1995) in 1995 and Stargate SG-1 (1997) from 1997 to 2005.