Launched in 2005, the Illinois Integrated Assessment (IA) process is designed to provide better information about child and family strengths, support systems, and service needs. In this study, we examine the extent to which fathers--stepfathers, putative fathers, legal fathers, adoptive fathers, or biological fathers--were interviewed as a part of the IA process and the factors associated with fathers being interviewed. An analysis of over 9,000 completed IA cases indicates that when both parents were interviewed as part of the IA, children were significantly more likely to be reunified than when only one or neither parent was interviewed. The information in the IA reports provide a rich description of the ecology of these families, covering such topics as housing, education, employment, finances, informal supports, domestic violence, substance use, and criminal behavior. We draw on a sample of IA reports as well as caseworker interviews to provide rich descriptions of the complex circumstances and family roles of fathers, examine the extent to which case service plans reflect the assessment recommendations and fathers' circumstances, and explore caseworkers' experiences in engaging or working with fathers. Findings from this study are discussed with respect to implications for ongoing efforts by the child welfare system to engage fathers and effectively deliver or arrange services that address fathers' needs and improve child and family well-being. Three appendices are included: (1) Factors Associated with Interviewing Neither, One or Both Parents; (2) Comparison of IA and SP Recommendations; and (3) Survival Analysis of Reunification. (Contains 8 tables, 3 figures and 7 footnotes.)