As with most NYC-based actors in the 50s, Kiley began his small screen career in live productions, but it was not until he had reached middle-age that his TV work increased momentum. He won his first Emmy for his portrayal of the patriarch of an Australian family in the ABC miniseries "The Thorn Birds" in 1983. Kiley went on to earn raves as the husband of a woman (Joanne Woodward) diagnosed with Alzheimer's Disease in "Do You Remember Love?" (CBS, 1985). He was another patriarch a widower coping with life alone and helping his children stabilize their own lives, in the award-winning miniseries "A Year on the Life" (NBC, 1986) and its spin-off (NBC, 1987-88), which earned him a second Emmy. After making recurring appearances on NBC's "The Cosby Mysteries" (1994-95), Kiley earned a third Emmy for his turn as the irascible father of Jill Brock (Kathy Baker) in an episode of the CBS drama "Picket Fences".
Kiley's film work was more sporadic. He made his debut in 1951 in "The Mob", was a supporting player to Richard Widmark in the excellent spy thriller "Pickup on South Street" (1953) and as the member of the faculty who thinks he can reason with the hoodlums in "The Blackboard Jungle" (1955). After the 50s, his film appearances became infrequent. Among his more notable later roles were the pilot in the screen musical version of "The Little Prince" (1974), Diane Keaton's ill-tempered father in "Looking for Mr. Goodbar" (1977) and a doctor in "Patch Adams" (1998, his final film).
Often, the actor could be heard rather than seen, employing his sonorous baritone as a narrator. For instance. Kiley could be heard as the tour voice in "Jurassic Park" (1993) and in numerous TV commercials. He also provided the narration for documentary programming, including "National Geographic Specials", "Nova", "Planet Earth" as well as hundreds of nature, historical, and informative specials and reality shows on public television, broadcast networks, and cable channels (e.g., The Discovery Channel, The Learning Channel).