Experimental determination of $V_{us}$ from kaon decays
  During the last few years, new experimental and theoretical results have allowed ever-more-stringent tests of the Standard Model to be performed using kaon decays. This overview of recent progress includes updated results for the evaluation of the CKM matrix element $V_{us}$ and related tests of CKM unitarity from experimental data on kaon decays. 
Matthew Moulson
hep-ex hep-ph