Nelson Smock Riddle, Jr. (June 1, 1921 - October 6, 1985) was a well-known American bandleader, arranger and orchestrator whose career spanned from the late 1940s until the early 1980s. Riddle is perhaps best known for his 1950s work for Capitol Records, providing jazzy big-band style arrangements to accompany such vocalists as Frank Sinatra, Dean Martin, Nat King Cole, Judy Garland, Peggy Lee, Louis Prima and Keely Smith. Later, his arranging talents were also used by Ella Fitzgerald, Shirley Bassey, Matt Monro, Linda Ronstadt, and others. His arrangements are characterized by innovative orchestration with counter melodies and instrumentation that express the emotions of each verse of a song.

Interestingly, whilst arranging the Sinatra albums he received the pay of a band sideman, which was enhanced by Capitol when Nat King Cole discovered the anomaly and insisted he receive fair remuneration.