An upgrade of EUROSID-1, the side impact dummy used in the European Union Side Impact Directive 96/EC/27, was recently developed by TNO to address dummy response issues raised by industrial and governmental bodies, in particular, the flat-top anomaly in the rib deflections. NHTSA is evaluating the ES-2 dummy, the upgraded EUROSID-1, to assess its performance in the FMVSS 214 test configuration. This paper presents results from NHTSAis testing of the ES-2 including high mass pendulum impactor tests using three proposed rib designs, biofidelity sled tests comparing the ES-2 and U.S. SID, and full scale side impact tests.