Robert Hammond Patrick (born November 5, 1958) is an American actor. Known for portraying villains and honorable authority figures, he is a Saturn Award winner with four other nominations.

Patrick dropped out of college when drama class sparked his interest in acting, and entered film in 1986. After playing a supporting role in Die Hard 2 (1990), he came to prominence as the T-1000, the antagonist of Terminator 2: Judgment Day (1991)—a role he reprised for cameo appearances in Wayne's World (1992) and Last Action Hero (1993). His other film credits include Fire in the Sky (1993), Striptease (1996), Cop Land (1997), The Faculty (1998), Spy Kids (2001), Charlie's Angels: Full Throttle (2003), Ladder 49 (2004), Walk the Line (2005), Flags of Our Fathers (2006), We Are Marshall (2006), Bridge to Terabithia (2007), The Men Who Stare at Goats (2009), and Safe House (2012).

In television, Patrick played FBI Special Agent John Doggett in The X-Files, Colonel Tom Ryan in The Unit, DHS agent Cabe Gallo in Scorpion, and Auggie Smith / White Dragon in Peacemaker. He has played ongoing roles in series such as The Outer Limits, The Sopranos, Elvis, Burn Notice, Last Resort, Sons of Anarchy, its spin-off Mayans M.C., and From Dusk till Dawn: The Series.

Described by The Guardian as a character actor, AllMovie journalist Tracie Cooper wrote that, by the conclusion of The X-Files in 2002, Patrick had developed a "solid reputation within the industry", with critics, fans and co-stars alike praising his "work ethic, personality, and consistent performances." Actor and director Jason Bateman described Patrick as "one of the great heavies."

Early life
Patrick was born in Marietta, Georgia, on November 5, 1958, and raised there, as well as in Boston, Massachusetts, Dayton, Ohio, Detroit, Michigan, and Bay Village, Ohio. He is the eldest of five children born to Nadine and Robert M. Patrick, and is of Scots-Irish and English descent. His brother, Richard, is best known as the lead singer for the rock band Filter.

He did not start to pursue an acting career until his mid-twenties. During his childhood, he did not like to act; in third grade, he refused to wear a pair of green tights required for Peter Pan. He graduated from Farmington High School in Farmington, Michigan in 1977. He was a track and field and football athlete at Bowling Green State University. He dropped out before graduating when he found an interest in drama and acting. After leaving college, Patrick worked as a house painter and continued as such until a boating accident in 1984 in Lake Erie. He swam for three hours in order to save others still stranded on the accident site, and nearly drowned in doing so. After the accident, he moved to Los Angeles at age 26. His main income during his first years was as a bartender, and he often lived in his car, before being cast in his first film roles.