The ATLAS muon trigger system is used to identify LHC proton collision events of interest to both Standard Model measurements and searches for new physics. Composed of both hardware(Level-1) and software (High-Level Trigger) components, the trigger system was successfully optimized during Run 2 to provide high efficiencies while maintaining sufficiently low trigger
rates. These proceedings provide a brief description of the design performance of the ATLAS muon trigger system during Run 2. Several improvements which have been developed for Run 3 are also summarized.