The level of side impact protection provided currently by passenger vehicles has been examined in a series of crash tests performed following FMVSS 214 dynamic testing protocols, but employing EuroSID 1 and BioSID crash test dummies. The results are compared with those of earlier tests, performed by NHTSA, of identical vehicle models with US SID dummies. All three dummy designs produced similar vehicle performance rankings and pass/fail ratings based on TTI and peak pelvic acceleration values. Assessments of thoracic injury potential based on TTI typically showed good agreement with those provided by deflection based criteria. Significant loading of the abdomen was observed in all tests of production vehicles, including those which produced extremely low TTI values. Side interior designs or changes which provide low TTI values are not necessarily consistent with those required to minimize injury potential to the abdomen. The results of tests on modified vehicles show, however, that it is possible substantially to reduce acceleration, deflection and force responses by very modest changes in the design of production vehicles.