This study finds that the break-even point for child safety seat misuse reduction programs and vehicle and seat design improvements is $121 a year per child seat in use, annual misuse reduction program cost is $6, and Lower Anchors and Tethers for Children (LATCH) cost $13 annually per seat in use (in 2004 dollars). To estimate societal injury cost savings we compared tow-away crash outcomes for children ages 0-4, traveling in child seats in the back of passenger vehicles in 1984-1986 vs. 1999-2005. Both injury frequency and severity were compared and entered into the calculation of mean injury costs.