The number of children in child welfare care has increased from 10,000 in the early 1990s to over 18,000. Ontario spends over $1.1 billion a year on direct child welfare services, more than twice as much as spent in the late 1990s, with the majority of these resources spent on investigation instead of treatment. In response to this situation, Differential Response models, sometimes called alternative, multiple or integrated system responses, have been implemented in the US, Australia and Canada and are all at the beginning stages of systematic evaluation. These models will help prevent maltreatment cases from becoming ongoing protection cases, or the children ending up in out of home or community placements, and reduce the amount of time in Children's Aid Society care. This research will show the benefits and costs of a Differential Response approach to Children's Aid Society care, specifically in the Hamilton-Niagara Region