Hadronic Weak Interactions of Light Quarks

In this review, three subjects are discussed: a phenomenological application of lattice predictions to $K^0$–${\bar{K}}^0$ mixing in Super Symmetry; a discussion of the non-perturbative renormalization methods for four-fermion operators and a new approach to extract weak matrix elements in effective theories denoted as OPE without OPE (operator product expansion without operator product expansion)