  The feasibility of measuring chiral-odd parton distribution functions in
polarized Drell-Yan and semi-inclusive experiments has renewed theoretical
interest in their study. Not long ago we presented an analysis of the
transversity distribution functions using models of hadron structure and
Leading Order evolution. In the meantime Next to Leading Order evolution
equations for $h_1$ are also available. We here present a comparison between
the LO and the NLO results which confirms our previous conclusions.
