Kate Nelligan (born Patricia Colleen Nelligan; March 16, 1950) is a Canadian retired actress, who was celebrated for her commanding performances and versatility. She trained at Glendon College in Toronto and London's Central School of Speech and Drama before launching her professional career in 1972 with the Bristol Old Vic, appearing in productions like Barefoot in the Park. Nelligan rose to prominence in the UK with the National Theatre in plays such as David Hare's Knuckle (1974) and Tales from the Vienna Woods (1977), alongside early television roles in The Onedin Line and her film debut in The Romantic Englishwoman (1975).

In the early 1980s, she relocated to New York, where she garnered critical acclaim on Broadway, earning four Tony Award nominations for Plenty (1983), A Moon for the Misbegotten (1984), Serious Money (1988), and Spoils of War (1989). Her film career flourished with standout roles in Eye of the Needle (1981) opposite Donald Sutherland, Without a Trace (1983), and later Frankie and Johnny (1991), for which she won a BAFTA for Best Supporting Actress; she also received an Academy Award nomination for The Prince of Tides (1991). Other notable films include Wolf (1994), U.S. Marshals (1998), and The Cider House Rules (1999).