Annually, over 3.8 million sports and recreation-related concussions occur in the United States. Youth athletes represent a large portion of the injured, and some obtain catastrophic injuries or die due to improper evaluation or management. Currently, 9 states have passed laws that require the education of key stakeholders and list requirements about removal from and return to play. To provide practice-based guidance to states considering similar legislation, the CDC National Center for Injury Prevention and Control is conducting an evaluation of the "return to play" laws in Washington and Massachusetts. This presentation will examine how values shape the participation of key stakeholders--athletes, public health practitioners, educators, and coaches--in the implementation of each state's legislation. Discussion will address unintended consequences, barriers to implementation, and offer suggestions for utilizing stakeholder values to promote effective implementation that eventually leads to a reduction in youth concussions. #2011Conference #AdvocacyandPolicyChange #policyimplementationevaluation