Steps towards full two-loop calculations for 2 fermion to 2 fermion processes: running versus pole masses schemes

Recent progress in the calculation of the two-loop on-shell mass counterterms within the electroweak Standard Model (SM) for the massive particles is reviewed. We are in progress of developing a package for full two-loop SM calculations of 2 → 2 fermion processes with emphasis on the analytical approach, where feasible. The complete two-loop on-shell renormalization is implemented. Substantial progress has been made in calculating the master integrals. We are able to compute up to a few thousands of diagrams of very complex mass structure in an efficient and stable manner.