After a few low-profile appearances in television pilots and sitcoms, including The Facts of Life, Roseanne, and the drama Sisters, as well as in the film Attack of the Killer Tomatoes (1988), Clooney finally gained notice as the handsome and commitment-phobic Dr. Doug Ross in the television hospital drama, ER (1994). After being named one of the Fifty Most Beautiful People, Best-dressed Star and Sexiest Man Alive by People magazine in 1996-97, he again turned to film, making One Fine Day with Michelle Pfeiffer in 1996, and turning in a critically acclaimed performance in Quentin Tarantino’s From Dusk Till Dawn (1996).

In 1997 he became the fourth incarnation of the caped crusader in Joel Schumacher’s Batman and Robin, reportedly earning $10 million for his role as Batman. He was said to command the same salary for the critic-favorite 1998 film Out of Sight, directed by Steven Soderbergh, which was based on the Elmore Leonard novel. He has also appeared in The Peacemaker(1997) with Nicole Kidman, and Terrence Malick’s The Thin Red Line (1998).

In early 1999 ER suffered its own kind of trauma when Clooney left the show in its fifth season; its immediately-lower ratings reflected his absence, and plans for him to return in guest appearances in the new season were begun. Since his departure from the small-screen, Clooney has kept busy, starring in eight films in 1999 and 2000, including Three Kings (1999), the Coen Brothers’ Oh Brother Where Art Thou? (2000), and the adaptation of Sebastian Junger’s A Perfect Storm (2000). In 2001, he took the lead in Steven Soderbergh's all-star Ocean's Eleven, followed by the same director's Solaris in Decemeber 2002.

In January 2003, Clooney made his directorial debut in Confessions of a Dangerous Mind, which tells the story of game show king Chuck Barris. He is next due to star in Joel Coen's Intolerable Cruelty opposite Catherine Zeta-Jones. Clooney also announced that he will re-team with Soderbergh for the sequel Ocean's Twelve, as well as for a remake of the hit Argentinean thriller Nine Queens.

Clooney, currently single, was married to Talia Balsam in 1989 and divorced in 1992.