The CMS experiment uses a sophisticated two-level triggering system composed of hardwarebased Level-1 Trigger, and a software-based High Level Trigger to select 1 kHz of events out
of 40 MHz for later analysis. A new Level-1 trigger architecture improves the data taking performance at high luminosity experienced during Run II. The upgraded muon trigger increases
the redundancy of the three muon detectors - Cathode Strip Chambers (CSC), Drift Tubes (DT),
and Resistive Plate Chambers (RPC) - by combining information in the muon track finders with
new track reconstruction, which yields a better efficiency and lower rates. The upgraded muon
trigger system and the algorithms designed to select events for both precision measurements and
new physics searches are described. The performance of the upgraded muon trigger system is
demonstrated using proton-proton collision data collected in Run II.