Abstract
I review kaon decays. I introduce the flavor problem and possible solutions. Very rare kaon decays like [see formula in PDF] are very important to this purpose: we study also [see formula in PDF] where chiral dynamics is important to disentangle short distance effects. We have also studied lepton flavor (universality) violation in rare kaon decays and the Bardeen Buras Gerard approach to describe the [see formula in PDF] form factor.