The survey found that in all 15 States there are policies or practice protocols which formally guide the implementation of and child welfare practice in a differential response system. All respondents indicated that assignment to either the traditional investigation response or the noninvestigation family assessment response was based on specific criteria. While the general differential response approach nationwide embraces key values of family engagement and service provision, jurisdictions vary in their conceptual delineation of who should receive which options. With the data from the study as a foundation from which to base future inquiry, as well as the questions they raise, there is much opportunity as well as need to gain additional understanding about the impacts of differential response on child welfare systems, including frontline practice, outcomes for children and families, and impact on worker and family satisfaction. Building on the Federal Government’ 2003 National Study of Child Protective Services Systems and Reform Efforts, the American Humane, and the Child Welfare League of America collaborated to conduct a national study of differential response in child welfare in 2005-2006. The study attempted to achieve definitional clarity and distinguish among the many child protection reforms across the Nation’s State and county child welfare systems. This paper presents a summary of the results of the study with the following States represented: Alaska, Florida, Hawaii, Kentucky, Louisiana, Minnesota, Missouri, North Carolina, Oklahoma, Pennsylvania, Tennessee, Virginia, Washington, West Virginia, and Wyoming. Tables, references