CP violation in kaon decays
  We review the Standard Model predictions of CP violation in kaon decays. We present an elementary introduction to Chiral Perturbation Theory, four--quark effective hamiltonians and the relation among them. Particular attention is devoted to $K\to 3\pi$, $K\to 2\pi \gamma$ and $K\to \pi \bar{f} f$ decays. 
G. D'Ambrosio and G. Isidori