Future charged kaon decay experiments

Future experiments aiming to perform precise measurement of rare kaon decays are briefly reviewed; in particular those experimental programs designed to gain new insight on the Unitarity triangle and on the CKM mechanism by observing an hundred of events of the K+→π+νν-bar decay are considered. This rare process, BR ∼10-10, is computed with very small theoretical errors, providing one of the cleanest tests of the Standard Model (SM) and, possibly, it could give some hints on the flavour structure of New Physics. A target accuracy of order 10% should be reached, thus making experiments in this field very challenging projects, expecially with respect to backgrounds suppression, particle identification capabilities and detector efficiency, while keeping costs and complexity at a reasonable level