This paper describes a social-developmental approach to interventions in chronic illness using naturally occurring processes of change during family life-cycle transitions to promote more positive developmental outcomes. Clinical interventions can help build resilience by creating a therapeutic collaboration designed to help patients improve their use of existing and new resources in multiple systems. They can then better meet demands of the illness as it impacts on shared development. A case example of a 13-year-old daughter with complex, chronic health problems and developmental disabilities illustrates clinical interventions designed to promote family resilience during the entry into adolescence and a transition in schooling. This approach involves focusing on the family's own definition of the current problem and relevant history, constructing a multidimensional, coherent story of the illness and its impact that recognizes stressors yet highlights strengths, and normalizing their strategies for stability under circumstances of developmental stress. These interventions with mother, daughter, and family helped improve health efficacy, communication toward mutual understanding and shared problem solving, and better use of existing and new resources to enhance current and future developmental adaptation. © 2002 Wiley Periodicals, Inc. J Clin Psychol/In Session 58: 1375–1384, 2002.