We report on progress in our programme of non-perturbative improvement and renormalization of operators composed of Wilson fermions based on correlators in position space. We concentrate on the CLS $N_f=2+1$ ensembles. We discuss an updated determination of $b_J$ and $\tilde{b}_J$ improvement coefficients. We introduce a new strategy for non-perturbative renormalization which alleviates the window problem and we present results for the renormalization constants of flavor non-singlet quark bilinear operators in the scalar, pseudoscalar and axial channels. Finally we mention the relevance of lattice artifacts at one-loop lattice perturbation theory.

Standard Model Parameters and Renormalization