This report describes the decision-making model that provides the theoretical framework being developed by the Early Childhood Research Institute on Measuring Growth and Development (ECRI-MGD) in a 5-year project to generate a set of common child and family indicators that can be used within a comprehensive system of service delivery for young children with disabilities, birth to age 8. The report first looks at the current model of assessment and service delivery in early intervention and limitations of the model. These limitations include lack of linkage across assessment phases, lack of linkage to long-term goals, and lack of theoretical framework for decision making. It then explains the rationale for and components of the Problem-Solving Model of decision making. It identifies theoretical assumptions and the two types of assessment tools used, Individual Growth and Development Indicators and Exploring Solutions Assessments. A table provides an overview of the ECRI-MGD Problem-Solving Model including the decision-making phase, questions, and assessment tools and procedures utilized. The final section discusses similarities and differences between the ECRI-MGD Problem Solving Model and the current model of assessment in early intervention. (Contains 21 references.) (DB)