In this paper the results of an evaluation of a multi-site, out-of-school-time program are presented. A particular focus will be on evaluation findings concerning the separate and combined impacts of site (or contextual) characteristics and individual participant differences in determining program outcomes. In the aftermath of Hurricanes Katrina and Rita, an out-of-school-time, collaborative program, known as "Houston's Kids," was implemented with the intention of addressing the needs of displaced and other at-risk youth in a single community. An outcomes evaluation was conducted to assess the program's effects on developmental assets as well as on academic achievement among the approximately 375 individual kindergarten through intermediate school participants. True panels of data that tracked changes in the same individual participants over a school year were employed as were data on a sample of control or “comparison” subjects. Hierarchical and multiplicative statistical models were used to analyze the data.