  These lectures are an introduction to the subject of chiral effective
Lagrangians of the Standard Model and their applications, mostly in the sector
of non--leptonic kaon decays, with special emphasis on CP--violation. The first
lecture gives an introduction to the phenomenological description of the
$K^0-\bar{K}^0$ system and $K\ra \pi\pi$ decays. In the second lecture I give
an overview of the basic ideas behind the chiral perturbation theory ($\chi$PT)
--approach to hadron dynamics at low energies. The study of the weak
interactions of $K$--particles within the framework of $\chi$PT is the subject
of the third lecture. The fourth lecture is an overview of various models of
the QCD low--energy effective action which have been developed during the last
few years. The fifth lecture is dedicated to a discussion of the CP--violation
$\epsilon$ and $\epsilon'$ parameters, and to the study of the decay mode:
$K_{L}\ra \pi^{0}e^{+}e^{-}$.
