Marie-Alphonse-Nicolas-Joseph Jongen (1873–1953) was a Belgian composer and organist, known for his contributions to early 20th-century classical music. His works primarily fall within the genres of symphonic music, chamber music, and organ compositions. Jongen was particularly influential in the development of organ music, showcasing his prowess with rich harmonies and innovative textures. Notable works include the "Symphony Concertante" for organ and orchestra, which highlights his mastery of the organ as both a solo and orchestral instrument. His "Sonata Eroica" for organ and various chamber pieces, such as the "Quintette for Winds," also reflect his melodic skill and structural ingenuity. Jongen was a prominent figure in music education, serving as a professor at the Royal Conservatory of Brussels, where he influenced a generation of musicians. His impact on music can be seen in the way he integrated French and Belgian musical traditions, merging them with contemporary trends of his time. Jongen's work remains significant in the repertoire of organists and continues to be performed, illustrating his lasting legacy in the classical music canon.