S. Kelly is a contemporary American jazz arranger and composer, renowned for their innovative contributions to large ensemble jazz. Kelly's distinctive style seamlessly blends traditional big band aesthetics with modern harmonic and rhythmic sensibilities, creating vibrant and sophisticated soundscapes. Their work has been featured by prominent university jazz orchestras and professional ensembles, and they are particularly recognized for their intricate voicings and imaginative use of counterpoint. Kelly's arrangements have been praised for their ability to challenge musicians while remaining accessible and engaging for audiences, solidifying their reputation as a significant voice in modern jazz band literature.