2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/49195We review some recent theoretical results on rare kaon decays. Particular attention is devoted to establish the short distance (direct CP violating) contribution to K_L => π^0 e \bar{e}. This is achieved by a careful study of the long distance part. As byproduct, we discuss interesting chiral tests.7 pages LaTeX, Talk given at La Thuile Conference, 28th February- 7th March '99. Erratum in References correctedHigh Energy Physics - Phenomenologytext