Nicolas Slonimsky (1894–1995) was a Russian-American conductor, composer, and musicologist, renowned for his contributions to contemporary music and music theory. His genre-spanning work primarily focused on classical music, but he had a significant impact on various avant-garde movements. Slonimsky is best known for his role as a conductor and for his extensive writings on music, including the influential "Thesaurus of Scales and Melodic Patterns," which has been widely used by composers and musicians for its innovative approach to scales and melodic construction. He also authored the "Lexicon of Musical Invective," a critical study of music reviews, which highlighted the frequently negative reception of new music. His impact on music extended beyond his written works; he was an advocate for modern composers, including Aaron Copland, Igor Stravinsky, and Leonard Bernstein, and played a crucial role in promoting their music. Slonimsky's lifelong commitment to exploring and documenting the evolution of music has made him a pivotal figure in 20th-century music history, influencing generations of musicians and scholars. His legacy continues to resonate in the study and performance of contemporary music.