The purpose of this study was to compare the dynamic response of rear-facing child restraint systems (RFCRS) installed on the CMVSS 213 sled bench and a selection of vehicle seats. Thirty-six sled tests were conducted: three models of rear facing CRS with an anthropomorphic test device (ATD) representing a 12 month old child (CRABI) were affixed via lower anchors (LATCH), 3 point belt without CRS base, and 3 point belt with CRS base to one of three vehicle seats or the CMVSS 213 bench seat. All CRS were subjected to an identical sled acceleration pulse. Two types of matched pair analysis: "bench-to-vehicle" and "method of attachment" were conducted. Statistically significant differences were observed in the kinematic responses of the ATD and the CRS.This is the first study to quantify differences between the regulatory bench and vehicle seats on a system level and evaluate the influence of attachment method. Our results show that the difference in RFCRS forward excursion between 3-point belt with base and LATCH installations was between 1 and 7 percent on the bench and 22 to 76 percent on the vehicle seats. When evaluating the dynamic performance of RFCRS, the use of real vehicle seats from vehicles that commonly carry children may provide valuable insight. The findings would require further confirmation using a broader selection of RFCRS and vehicle seats, before generalizable conclusions can be drawn.