Abstract
After briefly reviewing the structure of the convex sets of POVM's and channels in finite dimensions, we will consider maps between different types of convex sets, corresponding to different kinds of quantum information processing, e. g. quantum calibration, programmable channels and POVM's, universal POVM's, pre-processing and post-processing of POVM's. In particular, we will focus attention on programmability of POVM's and pre-processing, introducing the problem of "clean POVM's", and concluding with a list of open problems.