Reggio is most known for his Qatsi trilogy, which includes the films Koyaanisqatsi, Powaqqatsi, and Naqoyqatsi. All of the film titles are taken from the Hopi language; Koyaanisqatsi meaning "life out of balance," Powaqqatsi meaning "life in transformation," and Naqoyqatsi meaning "life as war." In 1995 he directed the short feature entitled Evidence that featured, like the Qatsi Trilogy, a soundtrack composed by his friend Philip Glass.