  We review the current status of the field of rare kaon decays. The study of
rare kaon decays has played a key role in the development of the standard
model, and the field continues to have significant impact. The two areas of
greatest import are the search for physics beyond the standard model and the
determination of fundamental standard-model parameters. Due to the exquisite
sensitivity of rare kaon decay experiments, searches for new physics can probe
very high mass scales. Studies of the k->pnn modes in particular, where the
first event has recently been seen, will permit tests of the standard-model
picture of quark mixing and CP violation.
