Child restraint performance in frontal and lateral crash simulations is presented and discussed based upon tests conducted on the Calspan HYGE acceleration sled. Differing acceleration pulses for frontal tests were used to evaluate the pulse shape effect upon the child restraint systems. Two types of three year old size ATDs were used and restraint systems were intentionally improperly installed in an effort to ascertain the potential hazard to the child occupant from improper installation. Data obtained include head excursion, head and chest triaxial accelerations, HSI and CSI values for the ATDs. High speed movie coverage produced dummy kinematic results.Results of the study allow comparisons between the effects of different pulse shapes and the effects of different ATDs on restraint performance and comparisons in dynamic performance of the ATD/restraint complex under both proper and improper system installation.FMVSS 213 and Canadian P.C. 1977-1013 dynamic performance criteria are discussed in light of the findings of this study.This work was partially funded by Consumers Union of the U.S. and Consumer and Corporate Affairs - Canada.