  We present an update of a previous global analysis of the experimental data
on azimuthal asymmetries in semi-inclusive deep inelastic scattering (SIDIS),
from the HERMES and COMPASS Collaborations, and in e+ e- -> h1 h2 X processes,
from the Belle Collaboration. Compared to the first extraction, a more precise
determination of the Collins fragmentation function and the transversity
distribution function for u and d quarks is obtained.
