Responses to juvenile offending have swung between rehabilitative and punishment approaches since the 1960s. A shift back toward rehabilitation has been influenced by recent research on adolescence, adolescent decision making, and adolescent brain development. US Supreme Court decisions on juvenile sentencing have been influenced by them. Major changes from adolescence into early adulthood have been demonstrated in the frontal lobe and especially the prefrontal cortex, which helps govern executive functions such as self-control and planning. Compared with adults, adolescents are more impulsive, short-sighted, and responsive to immediate rewards and less likely to consider long-term consequences. Adolescents are thus less blameworthy than adults. Responses to juvenile offending should take account of malleable aspects of psychosocial functioning in a developmentally informed manner.