  Transverse momentum dependent parton distributions (TMDs) appear in many
scattering processes at high energy, from the semi-inclusive DIS experiments at
a few GeV to the Higgs transverse momentum distribution at the LHC. Predictions
for TMD observables crucially depend on TMD factorization, which in turn
determines the TMD evolution of the observables with energy. In this
contribution to SPIN2014 TMD factorization is outlined, including a discussion
of the treatment of the nonperturbative region, followed by a summary of
results on TMD evolution, mostly applied to azimuthal asymmetries.
