Afterschool programs (ASPs)—also called out-of-school time (OST) programs—include a variety of program types, structured in numerous ways, designed to affect a variety of outcomes. As the name implies, such programs generally occur outside of mandated school hours, although some programs classified as afterschool or out-of-school may be part of a larger program where elements are delivered during school hours. These may be delivered before school, in the afternoons once school has been dismissed, on weekends, or during the summer. Most current ASPs generally have one of three purposes, although these are not mutually exclusive: improving students’ academic performance, preventing problem behaviors from developing, and encouraging positive youth development (Lauer et al. 2006). ASPs have risen in popularity over the past decades as more women have moved into the workforce, and concerns about unsupervised children have grown. Research findings estimate that 35 percent of 12-year-olds are left by themselves regularly while their parents are at work. In fact, the gap between parent work schedules and child school schedules can total 20 to 25 hours per week (U.S. Department of Justice 2000). This unsupervised time is a risk factor for serious and violent behavior among youths. The evidence suggests that children “who are unsupervised during the hours after school are more likely to use alcohol, drugs, tobacco, receive poor grades, and drop out of school than those children who have the opportunity to benefit from constructive activities supervised by responsible adults” (U.S. Department of Justice 2000). Gottfredson, Gottfredson, and Weisman (2001) also find that youths who are unsupervised during afterschool hours are found to be more delinquent at all times, not only after school. Research has documented an association between parental supervision and lower levels of problem behaviors (Apsler 2009). Also justifying the need for more programs to address this supervision gap is the apparent peak of violent crime in the 4 hours following the end of the school day (roughly 2–6 p.m.). Data from the FBI National Incident-Based Reporting System (NIBRS) shows that crimes among youth peak between 3 p.m. and 4 p.m. (Snyder and Sickmund 1999). Other recent research, though, has used victimization surveys, such as the National Crime Victimization Survey, and reached the conclusion that the dramatic peak in crime is, in fact, more modest than official data sometimes indicates and that “juveniles are disproportionately victimized while at school relative to the percentage of time they spend at school” (Soulé, Gottfredson, and Bauer 2008, 625). A recent study of Maryland students based on victimization surveys shows that juvenile victimization and delinquency peak during school hours, though more serious violent offenses are higher after school (Soulé, Gottfredson, and Bauer 2008). One reason for the discrepancy in findings based on NIBRS and survey data is that crime that occurs in school or on the way to and from school often does not appear in official police records (Gottfredson, Gottfredson, and Weisman 2001). Where ASPs were once primarily viewed as a safe haven for youth when parents were unavailable for supervision, the growing emphasis on the need for improved academic performance and basic skills to succeed in the 21st century has transformed the vision of what ASPs can, and should, do for youth (Harvard Family Research Project 2008). ASPs’ potential led the federal government to become an active supporter of this growing movement. In 1994, Congress authorized the 21st Century Community Learning Centers program and increased funding for the centers from $40 million in 1998 to $1 billion in 2002. According to the original funding guidelines, these centers were to concentrate on providing academic and enrichment activities during afterschool hours; centers that included elements to help students reach state and federal standards were given extra consideration in the application process (James–Burdumy et al. 2005). The structure of funding changed in 2002 with the passage of No Child Left Behind, at which point funding began being distributed to states in proportion to allocation of Title I funds (James–Burdumy et al. 2005). As of fiscal year (FY) 2010, appropriations brought the total funding for the centers to $1.17 billion, an increase of $35 million over FY 2009. The funding of these programs has in crucial ways been disconnected from the evidence of program effectiveness (Fagan 2007). For instance, funding grew rapidly from 1994 to 1998 with little evidence about the effectiveness of ASPs. When an evaluation of the 21st Century Community Learning Centers was published in 2005 that demonstrated no academic improvements and increased negative behaviors by participants, Congress nonetheless continued to fund the centers in 2006 with approximately $1 billion (Fagan 2007). Although many continue to advocate for more ASPs, arguing that there is not enough supply to meet demand, some recent research has started to look at the match between supply and demand. Bodilly and Beckett examined this question in a 2005 report on OST programs. They found that most studies documenting unmet demand were highly flawed (e.g., they were based on unverifiable assumptions), and many studies, in fact, documented significant openings in extant programs. Low attendance is quite common in ASPs, and two studies that directly addressed this issue found that the ASP in question did not reduce the number of unsupervised youths (Apsler 2009; Weisman and Gottfredson 2001; James–Burdumy et al. 2005). Based on their examination, Bodilly and Beckett recommended that improving the quality of existing programs should take precedence over increasing their supply. Characteristics of Effective Programs One of the emerging aspects of evaluations of ASPs is the effort to identify what characteristics of programs make them most effective. Characteristics or components of effective programs include