After-school programs have become an increasingly integral component of youth services. Numerous federal, state, and local initiatives have been implemented or expanded recently, resulting in a broad array of school- and community-based programs. A growing number of peer-reviewed outcome studies and longitudinal evaluations suggest that thoughtfully developed after-school programs can lead to improvements in academic performance, social skills, and internalizing and externalizing behavior. Additional research attention is needed, however, to understand these influences and to decipher the underlying processes by which participation in after-school programs promotes positive outcomes. Such processes are likely to be as varied as the needs of particular young people, and they may range from simply keeping adolescents out of harm's way or improving grades to more profound shifts in developmental outcomes. Despite this range of purposes, there is growing consensus that caring youth-staff relationships may be a key determinant of both retention and success in these programs. In this article, the author reviews the literature as it pertains to youth-staff relationships in after-school settings. (Contains 1 figure and 36 notes.)