One of the most influential Hammond organists in jazz, Smith began as a pianist. He started playing in the Philadelphia area, where he also studied music in the late 1940s and early 1950s. He came to New York and appeared at the Cafe Bohemia in 1956, which sparked his national and international career.
Smith established a small group that had no bassist (he played the basslines himself with his feet on the organ pedals), but usually featured guitar and drums, as well as often adding a tenor sax. His principal associates included drummer Donald Bailey, guitarist Kenny Burrell, and saxophonist Stanley Turrentine.
The group recorded widely for the Blue Note label - not least because the company's co-proprietor Francis Wolff was a great Smith fan, and encouraged his career. Smith remains a master of the slow build, settling into a blues groove and adding excitement and tension over chorus after chorus.
In the late 1970s he briefly ran a club in Los Angeles, and his recording and touring career had a slightly bleak period in the mid-1980s, but he returned to form and to mastery of the international stage in 1989. In the 1990s he has been a firm favourite on the world club and festival circuit, with annual visits to London's Jazz Cafe among the fixtures in his calendar.
Smith worked to produce a distinctive sound on the Hammond, and his style is widely imitated, not least among the school of Philadelphia players who have emerged in his shadow.