Standing 6-feet-5-inches-tall, Fuller is frequently cast as weaselly executives, smarmy authority figures, and sometimes law enforcement officers. He may be recognized as nerdy television director Russell in Wayne's World, a spiteful mayoral aide in Ghostbusters II, the sleazy television executive and mastermind of the "Battle of the Tough Guys", Mr. Brell in No Holds Barred, a seedy real estate agent in Elvira, Mistress of the Dark, and power-abusing, egotistical NSC Director Robert Lindsey in the third season of Alias. Usually cast in comedic roles, Fuller played Werner Klemperer, who he resembles, in Paul Schrader's Auto Focus and Karl Rove on the TV satire That's My Bush!. He also portrayed Pacific Bell Retirement Fund Executive Walter Ribbon in The Pursuit of Happyness.
Fuller has also appeared in many television shows, including Knight Rider, Timecop, Quantum Leap, L.A. Law, Murder, She Wrote, Ally McBeal, Felicity, Malcolm in the Middle, The West Wing, Boston Legal, Boston Public, House, Monk, Desperate Housewives, the live action version of The Tick, Charmed, Carnivàle, My Name Is Earl, Ugly Betty, Glee, and the pilot episode of NewsRadio. He has had a recurring role as Woody the Coroner on Psych and on Supernatural, depicting an angel called Zachariah.
Beginning in the Fall 2010 Season, Kurt began appearing in the ABC Network series Better With You.
Fuller is married to actress Jessica Hendra (daughter of writer Tony Hendra) and has two children named Julia and Charlotte.