Chiral loop corrections and isospin violation effects in   epsilon'/epsilon
  A complete analysis of isospin breaking in $K\to 2\pi$ amplitudes, including both strong and electromagnetic corrections at next-to-leading order in chiral perturbation theory, has been achieved recently. We discuss the implication of these effects, together with the previously known chiral loop corrections, on the direct CP-violating ratio epsilon'/epsilon. 
A. Pich