Nonleptonic kaon decays: Theory vs. experiment

A review of the present experimental status of the rates and the Dalitz-plot slope parameters in CP conserving K --> 2pi and K --> 3pi decays is given. The corresponding isospin amplitudes have been determined by a common fit to the recent experimental data and have been used as an input to a consequent fit based on the constraints from O(p(4)) chiral Lagrangian. It has been found that the constraints of the chiral fit are well satisfied by the experimental data, allowing one to estimate the weak coupling constants and to predict the quadratic amplitudes in K --> 3pi decays and the one-loop strong rescattering phases. The consistency of the obtained weak coupling constants with weak resonance models has also been considered.