We present the result of a direct search for the decay KS → e e, obtained with a sample of ee → φ → KSKL events produced at DAΦNE, the Frascati φ–factory, for an integrated luminosity of 1.9 fb. The search has been performed using a pure KS beam tagged by the simultaneous detection of a KL interaction in the calorimeter. Background rejection has been optimized by using both kinematic and particle identification cuts. We find BR(KS → e e) < 9× 10 at 90% CL, which improves by an order of magnitude on the previous best limit.
