Born Alexander Viespi in Floral Park, Long Island, New York, Cord was stricken with polio at the age of twelve. His family then moved to Wyoming, where doctors advised him to take up horseback riding as a therapeutic exercise. This helped him recover from the disease by the time he was sixteen. Cord attended New York University in New York City and the American Shakespeare Theatre at Stratford, Connecticut.
Cord's first acting role was in the 1961 episode "The Mountain Men" of NBC's western television series, Laramie, starring John Smith and Robert Fuller. Cord's second role came a month later as Nino Sanchez in the episode "Winter Quarters" of a CBS western, Frontier Circus, starring Chill Wills. In 1962, he appeared as Larry Rome in the episode "Take a Number" of the NBC crime drama Cain's Hundred, starring Peter Mark Richman.
Cord subsequently appeared in the 1962 film, The Chapman Report, directed by George Cukor. He briefly enjoyed a leading man status on the big and small screen during the 1960s and 1970s, and starred or co-starred in mostly crime dramas, action films, and westerns.
In 1963 and 1964, Cord was cast as different characters in five episodes of the CBS drama/adventure series, Route 66, including the role of Michael in the two-parter, "Where There's a Will, There's a Way." In 1964, he played the part of Sam in the episode "If Your Grandmother Had Wheels" of another CBS drama, East Side/West Side, starring George C. Scott. During this same period, he appeared twice on the ABC police drama, Naked City, starring Paul Burke.
In 1965, Cord was cast as Jed Colbee in the episode "Survival" of the NBC western series, Branded, starring Chuck Connors as a United States Army officer trying to clear his name of a false accusation of cowardice.
In 1966, he played "the Ringo Kid," the role originally portrayed by John Wayne in John Ford's 1939 version, in a lavish all-star remake of Stagecoach, which arguably remains Cord's most heavily publicized endeavor.
Cord co-starred with Kirk Douglas in a 1968 crime drama, The Brotherhood, about a Mafia figure being sent to murder his own brother.
In 1974, Cord worked twice with Diana Muldaur: as a guest-star on her weekly NBC series Born Free and as her love interest in the motion picture Chosen Survivors, an apocalyptic horror film that acquired a cult status in subsequent years.
Cord is among a handful of actors to appear on both the original and revival versions of CBS's Mission: Impossible. Cord is also known to science fiction enthusiasts for having portrayed Dylan Hunt in the failed 1973 television pilot, Genesis II, which was created by Gene Roddenberry. In 1977, he starred as the title character in the epic western Grayeagle.
In 1972, he appeared as Pete Brown in the episode "The Sodbusters" of the long-running CBS western, Gunsmoke. In 1973, he played the role of Haynes in "The Night of the Long Knives" on the ABC crime drama, The F.B.I., starring Efrem Zimbalist, Jr. Between 1973 and 1976, he appeared in four episodes of NBC's Police Story. In 1979 and 1981, he appeared twice on ABC's romantic comedy, The Love Boat. In 1988, Cord was cast in an episode of the CBS detective series Simon and Simon; in 1988 and 1992, he appeared on CBS's Jake and the Fatman. He also appeared In an episode of "War of the World" series 1988. He appeared twice in another CBS crime drama, Murder, She Wrote, starring Angela Lansbury. In 1995, Cord played the character Larry Curtis in the episode "The Guardians" of the CBS crime drama, Walker, Texas Ranger, starring Chuck Norris.
Cord had three children, a daughter, Toni Aluisa, and two sons, Wayne Viespi and Demien Zachary Cord. Toni is the daughter of Mary Ann Hutchinson, whom Alex never married, and Wayne was the product of his first marriage. His second marriage was to actress Joanna Pettet, mother of Damien. His third marriage was to author Susannah Boye-Moller Cord.
Cord now resides in Fort Worth, Texas. Cord suggested that his long-term friend from Laramie, Robert Fuller, also move to Texas to raise horses. Fuller and his second wife, Jennifer Savidge, did relocate to Cooke County in 2004. Cord and Fuller often make appearances at western film festivals highlighting their continuing mutual interest in "The Spirit of the Cowboy."The Chapman Report (1962) - Bardelli
Synanon (1965) - Zankie Albo
Stagecoach (1966) - Ringo Kid
A Minute to Pray, a Second to Die (1968) - Clay McCord
The Brotherhood (1968) - Vince Ginetta
Stiletto (1969) - Count Cesare Cardinali
The Last Grenade (1970) - Kip Thompson
The Dead Are Alive (1972) - Jason Porter
Genesis II (1973) - Dylan Hunt
Chosen Survivors (1974) - Steven Mayes
Inn of the Damned (1975) - Cal Kincaid
Fire! (1977) - Packard Gentry
Grayeagle (1977) - Greyeagle
Beggarman, Thief (1979) - Evans Kinsella
Goliath Awaits (1981) - Dr. Sam Marlowe
Jungle Warriors (1984) - Nick Spilotro
The Dirty Dozen: The Fatal Mission (1988) - Dravko Demchuk
Uninvited (1988) - Walter Graham
Street Asylum (1990) - Capt. Bill Quinton
A Girl to Kill For (1990) - Mike / Wino
Joey Takes a Cab (1991)
Roots of Evil (1992) - Jake
CIA Code Name: Alexa (1992) - Victor Mahler
The Naked Truth (1992) - Herskovitz
Fire from Below (2009) - General Mark 'Stonewall' Jackson
Award of the London Critics Circle "Best actor" nominee
1966 Golden Laurel "New Faces" nominee
2001 Golden Boot Award winner