  In the list of the main items studied by the CERN COMPASS experiment there
are the transverse spin and momentum effects visible in the azimuthal
distributions of hadrons produced in the deep inelastic scattering. In the
years 2002-2004 COMPASS has collected data with a 6LiD target with the
polarization oriented transversely with respect to the muon beam direction for
about 20% of the running time; in 2007, COMPASS has used for the first time a
proton NH_3 target with the data taking time equally shared between
longitudinal and transverse polarization of the target. After reviewing the
results obtained with the deuteron, the new results for the Collins and Sivers
asymmetries of the proton will be presented.
