Weak Matrix Elements on the Lattice: Recent Developments in K-Physics

In this talk we present some recent developments in the calculation of weak matrix elements on the lattice. Lattice QCD is one of the few systematically improvable methods for computing them from first principles, and has proven a powerful and appealing approach. In spite of the successes, progress has been slow due to the presence of systematic effects, such as discretization and non-perturbative renormalization effects. In the following, we concentrate on the applications in K-physics of a recently introduced method for non-perturbative (NP) renormalization [1].