Beyond collinearity in the N(e,e'q) process

We discuss a few examples of structure functions for polarized, semi-inclusive scattering processes to show the richness of structure. Then we indicate how polarization and particle production can be used to study the quark and gluon structure of hadrons going further than the well-known parton densities and fragmentation functions. We also emphasize how single spin asymmetries in leptoproduction may shed light on explanations for single spin asymmetries in pion production in pp collissions.