Phenomenology of single transverse spin asymmetries
  A unified and consistent phenomenological approach to single transverse spin asymmetries in the framework of perturbative QCD, with the inclusion of a new class of spin and k_T dependent distribution and fragmentation functions, is presented. As an example, results on A_N(p(pol) p --> pion X) and P_Lambda(p p -->Lambda(pol) X) are shown. 
U. D'Alesio and F. Murgia (University and INFN, Cagliari, Italy)