H. Prego, a prominent figure in 20th-century jazz, was an American arranger whose innovative orchestrations shaped the sound of numerous big bands. Active from the 1930s through the 1960s, Prego was known for his sophisticated harmonic language and rhythmic vitality, often blending swing era exuberance with emerging bebop sensibilities. His arrangements for the orchestras of Duke Ellington and Count Basie are particularly celebrated, contributing iconic charts to their repertoires. Prego's meticulous attention to instrumental voicing and his ability to craft compelling soli passages significantly influenced the evolution of jazz ensemble writing, leaving an indelible mark on the genre.