Al Datz, an American jazz arranger active from the mid-20th century, was a pivotal figure in shaping the sound of big band and orchestral jazz. Known for his sophisticated harmonic language and innovative voicings, Datz crafted arrangements that blended traditional swing elements with emerging bebop sensibilities. His work with prominent bandleaders like Stan Kenton and Count Basie, and contributions to film scores, showcased his versatility. Datz's meticulous scores, often characterized by their intricate counterpoint and rich textures, significantly influenced the development of jazz ensemble writing, leaving a lasting legacy on the genre's orchestral landscape.