Motor vehicle injuries are a leading cause of injury and fatality to children. Child restraint systems can reduce injury, and their use has been a long-time focus of policy and programmatic work. During this time, there has been a marked increase in the number of children restrained in vehicles and a steady decline in vehicle-related injuries and fatalities to children. However, data reveal that children of color, compared to white children, are at greater risk of injury in motor vehicle crashes. To address needs of “the children left behind” from safety advances, the California Child Passenger Safety Initiative (CPSI) was launched in 2002 for 18 months. The CPSI was an innovative program designed to increase use and decrease misuse of child restraint systems among the most vulnerable children in California; i.e., children of color and children living in poverty. The CPSI was designed to: increase use of child safety seats among families who use public medical services at selected sites; decrease the rate of child safety seat misuse among these families; and increase knowledge of the then-new California child passenger safety seat law. This study compared survey and observation data for two samples of families with children age six and younger: a pre-intervention sample, and a post-intervention sample. Although the results of this study were mixed, dramatic increases in the use of certain child restraints and decreases in the misuse of others were observed. Implications for program replication are discussed.