By 1971, Hamlisch had earned his first Oscar nod for Best Original Song. He and Johnny Mercer collaborated on "Life Is What You Make It" for the soundtrack of "Kotch". While they won a Golden Globe Award, the pair lost the Academy Award to Isaac Hayes' "Theme from 'Shaft'". Within two years, however, Hamlisch made history by becoming the first individual to win three music Oscars in the same year for his work on adaptation of Scott Joplin rags for "The Sting" and his lush romantic score and title song (with lyrics by Alan and Marilyn Bergman) for "The Way We Were" (both 1973). Though capable in a number of idioms, Hamlisch is particularly adept at incorporating a pop sensibility into his compositions. Over the next two decades, he racked up an additional eight Academy Award nominations, mostly for the original songs for such films as "The Spy Who Loved Me" (1977), "Ice Castles" and "Same Time, Next Year" (both 1978), "Shirley Valentine" (1989) and "The Mirror Has Two Faces" (1996). The latter was co-written with rocker Bryan Adams, Adams' frequent collaborator Robert John 'Mutt' Lange and Barbra Streisand. Over the same period, Hamlisch has contributed haunting, effective scores to such features as "Ordinary People" (1980), "Sophie's Choice" (1982) and "Frankie & Johnny" (1991).
Hamlisch turned his attention to the Broadway stage in the early 70s, creating the music for the landmark Broadway show "A Chorus Line" (1975). While initial critical reaction overlooked the score in favor of the dazzling production and Michael Bennett's outstanding direction and choreography, audiences responded to the music. (The ballad "What I Did for Love" has become a modern standard.) He shared a Tony Award for Best Score (with lyricist Edward Kleban) and the Pulitzer Prize in Drama (with Kleban and book writers James Kirkwood and Nicholas Dante). "A Chorus Line" held the record as the longest-running musical in Broadway history until June 1997 when Andrew Lloyd Webber's "Cats" surpassed it.
Hamlisch's other stage outings have met with mixed receptions. "They're Playing Our Song" (1978) was loosely based on his romantic relationship with lyricist Carole Bayer Sager. With a book by Neil Simon, a driving, popular score by Hamlisch and Sager and star turns by Robert Klein and Lucie Arnaz, the show was a success. Not so his follow-ups. "Jean" (1983) was an ill-fated attempt to musicalize the life of actress Jean Seberg that failed in London and has never been produced in the USA. "Smile" (1986), based on Michael Ritchie's underrated 1975 feature, teamed him with Howard Ashman, but the results were mixed. The musical failed to sustain an appropriate tone, although Hamlisch wrote some lovely songs and one, "Disneyland", has become an audition staple. A 1993 reteaming with Neil Simon for a musicalization of "The Goodbye Girl" also fared badly with critics and audiences.
Hamlisch has found a secondary career as a guest conductor at American symphonies. In 1994, he served as the musical director for Barbra Streisand's long awaited return to live performing. For the filmed version of the concert which aired on both HBO and CBS, Hamlisch earned two Emmy Awards. Other TV credits includes the scores for such series as "Beacon Hill" (CBS, 1975) and the lovely nostalgic theme to "Brooklyn Bridge" (CBS, 1991-93) and such TV-movies as "The Entertainer" (NBC, 1976), "The Two Mrs. Grenvillles" (NBC, 1987) and "David" (ABC, 1988).