As a composer, percussionist, and conductor, William Kraft was a powerful shaper of contemporary music in Los Angeles. Kraft played percussion for the Los Angeles Philharmonic for 25 years, served as the orchestra's assistant conductor, and founded the Los Angeles Percussion Ensemble.

Kraft was born in Chicago on September 23, 1923, but grew up in San Diego. He served for three years in the U.S. Air Force at the end of World War II. Kraft attended Columbia University, earning a bachelor's degree in 1951 and a master's in 1954. His composition teachers included Jack Beeson, Henry Cowell, and Otto Luening, and he also studied percussion with Morris Goldenberg and Saul Goodman, and conducting with Rudolph Thomas and Fritz Zweig. Kraft spent several years as a freelance musician in New York, serving as an extra percussionist in the Metropolitan Opera Orchestra and crossing paths with various figures in the world of contemporary music. He became a percussionist with the Dallas Symphony in 1954 and moved to the Los Angeles Philharmonic the following year.

Kraft remained with the Philharmonic until his retirement in 1980, becoming principal timpanist in 1963. He did much to shape the orchestra's sound as it advanced to world-class status, and he was assistant conductor under Zubin Mehta for a time. In addition to the Los Angeles Percussion Ensemble, he founded the orchestra's New Music Group. In these positions, Kraft participated in and organized performances of much new music. He performed in premieres of major works by Stravinsky (under whose direction he played on a recording of L'histoire du soldat), Edgard Varèse, and Alberto Ginastera, and he was the percussion soloist in the American premieres of Stockhausen's Zyklus and Boulez's Le Marteau sans Maître. Kraft's own compositions were also widely heard. He wrote music in various languages in styles, pursuing serialism early in his career but later incorporating jazz and Impressionist influences. Kraft wrote much percussion music, and his Concerto No. 2 for Timpani: The Grand Encounter was commissioned by the San Francisco Symphony Orchestra and premiered under conductor Michael Tilson Thomas. The work was later played by the Hong Kong Philharmonic. He fulfilled commissions from major organizations and groups, including the Library of Congress, the Kronos Quartet, and United Airlines, which used his music to accompany the "Sky's the Limit" sculpture in a pedestrian passage at Chicago's O'Hare International Airport. Kraft wrote film scores, including those for Psychic Killer (1975), Avalanche (1978), Bill (1981), and Fire and Ice (1983). He served as chairman of the composition department at the University of California, Santa Barbara, from 1991 to 2002.

Kraft remained active after retirement; his Concerto for English Horn and Orchestra was commissioned by the Los Angeles Philharmonic and premiered in 2003, with Esa-Pekka Salonen conducting. Kraft died in Los Angeles on February 12, 2022, at age 98. By that time, more than 70 of his compositions had been recorded, including a 17-work series titled Encounters. ~ James Manheim, Rovi