Although targeted explicitly at changing adult behaviors and outcomes, welfare reform has direct implications for children. This guidebook details the results of the Project on State-Level Child Outcomes, designed to assist states in measuring child outcomes in the context of welfare reform programs. The guidebook is presented in three sections. Section 1 describes the Project study, in which representatives of state welfare agencies, federal government representatives, and researchers identified a set of child outcomes and agreed upon measurement techniques. This section also describes why child outcomes may be affected by adult-focused welfare programs, describes the conceptual model and common set of constructs, and describes several approaches to studying child well-being and the strengths and weakness of each approach. Section 2 presents the common core of constructs, including the rationales and sample questions to assess outcomes related to: (1) family income; (2) employment; (3) family formation and dissolution; (4) mother's psychological well-being; (5) absent parent involvement; (6) stability and turbulence; (7) consumption; (8) use of health and human services; (9) child care; (10) home environment and parenting practices; (11) children's education; (12) children's health and safety; and (13) children's social and emotional adjustment. Section 3 contains five appendices, including a copy of the child well-being survey and adult survey used in Florida, federal data sources, a description of surveys and measures from which sample measures were drawn. Contains approximately 125 references. (KB)