This paper summarizes the COMPASS Collaboration plans for its future beyond 2020, i.e. the
programme planned between CERN accelerator long shutdowns 2 and 3: measurements
using the muon beam on a transversely polarised deuteron target and proton radius measurement
in the elastic muon-proton scattering. A hint is also given at the long-term programme, foreseen
after the shutdown 3, with conventional muon and hadron beams as well as nonconventional, Radio Frequency-separated kaon and antiproton beams.