The purpose of this study was to investigate laryngeal movements in selected performance situations on alto saxophone. The specific research problems were to describe glottal activity in three selected musicians as they performed musical tasks with (1) various pitch ranges and registers, (2) fortissimo and pianissimo dynamic levels, (3) crescendo and decrescendo, (4) long tones with vibrato, and (5) legato and staccato styles of articulation. A fiberoptic laryngoscope was employed to gather the visual images, which were recorded on a sound synchronized video tape. A rating system was devised to provide graphic representation of the data. Results of the data indicated that the glottis was used as an airflow constrictor in certain performance situations, especially in pianissimo performance. Other conclusions were drawn, and suggestions for further research were discussed.