  The High-Luminosity LHC will deliver an unprecedented instantaneous
luminosity, requiring all experiments to upgrade their detectors to sustain the
higher background rates. The upgrade of the CMS Muon spectrometer includes
three stations of triple-GEM detectors. We present the status of the
commissioning and performance validation of the three GEM stations: GE1/1,
which is taking data in Run 3, GE2/1, for which the first detectors will be
installed in 2024, and ME0, which has undergone several performance studies for
high-rate and longevity and will start its mass production in 2024.
