I.A.L. Diamond (27 June 1920 - 21 April 1988) was a comedy writer in Hollywood during the 1940 and 50s. He was born Isadore Domnici in Ungheni, Romania, was referred to as "Iz" in Hollywood, and was known to quip that his initials stood for "Interscholastic Algebra League".

In 1957 Diamond began a collaborative relationship with Billy Wilder on the movie Love in the Afternoon. From there, the pair had a string of hits with Some Like It Hot, The Apartment (which won an Academy Award for Best Screenplay), One, Two, Three, Irma la Douce, the Oscar-nominated The Fortune Cookie and The Private Life of Sherlock Holmes.

Diamond died in Beverly Hills, California in 1988.

Filmography

as Writer

• Buddy Buddy (1981)
• Fedora (1978)
• The Front Page (1974)
• Avanti! (1972)
• The Private Life of Sherlock Holmes (1970)
• Cactus Flower (1969)
• The Fortune Cookie (1966)
• Kiss Me, Stupid (1964)
• Irma la Douce (1963)
• One, Two, Three (1961)
• The Apartment (1960)
• Some Like It Hot (1959) (screenplay)
• Merry Andrew (1958)
• Love in the Afternoon (1957)
• That Certain Feeling (1956)
• Something for the Birds (1952)
• Monkey Business (1952)
• Let's Make It Legal (1951)
• Love Nest (1951)
• It's a Great Feeling (1949) (story)
• The Girl from Jones Beach (1949)
• Two Guys from Texas (1948)
• Romance on the High Seas (1948) (additional dialogue)
• Always Together (1948)
• Love and Learn (1947)
• Never Say Goodbye (1946)
• Two Guys from Milwaukee (1946)
• Murder in the Blue Room (1944)

as Associate Producer

• Fedora (1978)
• The Private Life of Sherlock Holmes (1970)
• The Fortune Cookie (1966)
• Kiss Me, Stupid (1964)
• Irma la Douce (1963)
• One, Two, Three (1961)
• The Apartment(1960)
• Some Like It Hot (1959)