'''Stephen Michael Reich''' (; born October 3, 1936) is an American composer who, along with La Monte Young, Terry Riley, and Philip Glass, pioneered minimal music in the mid to late 1960s.Mertens, W. (1983), ''American Minimal Music'', Kahn & Averill, London, (p.11).Michael Nyman, writing in the preface of Mertens' book refers to the style as "so called minimal music" (Mertens p.8)."The term 'minimal music' is generally used to describe a style of music that developed in America in the late 1960s and 1970s; and that was initially connected with the composers La Monte Young, Terry Riley, Steve Reich, and Philip Glass." Sitsky, L. (2002), ''Music of the twentieth-century avant-garde: a biocritical sourcebook,''Greenwood Press, Westport, CT. (p.361)

His innovations include using tape loops to create phasing patterns (for example, his early compositions ''It's Gonna Rain'' and ''Come Out''), and the use of simple, audible processes to explore musical concepts (for instance, ''Pendulum Music'' and ''Four Organs''). These compositions, marked by their use of repetitive figures, slow harmonic rhythm and canons, have significantly influenced contemporary music, especially in the US. Reich's work took on a darker character in the 1980s with the introduction of historical themes as well as themes from his Jewish heritage, notably the Grammy Award-winning ''Different Trains''.

Reich's style of composition influenced many composers and groups. Writing in ''The Guardian'', music critic Andrew Clements described Reich as one of "a handful of living composers who can legitimately claim to have altered the direction of musical history". The American composer and critic Kyle Gann has said Reich " considered, by general acclamation, America's greatest living composer".