Obesity is a prevalent health behavior that is difficult to treat because of its complexity, constraints on provider time, and negligible insurer reimbursement. In this comparative case study the authors describe two obese women's weight loss and lifestyle change efforts while enrolled in a nine-month, multidisciplinary weight loss program. The researchers conducted three semistructured interviews during six months. Eight major themes were identified: (1) support networks. (2) internalization/externalization, (3) routines, (4) relapse, (5) change in perspective, (6) reward/punishment, (7) emotional issues, and (8) life balance. These themes parallel Johnson's three-stage theory of cognitive restructuring. (See Johnson, 1990, "Restructuring: An Emerging Theory on the Process of Losing Weight." Journal of Advanced Nursing, 15, 1289-1296.) Researchers reveal that complex health problems are replete with social and psychological factors that may undermine treatment success. Understanding a client's experience while attempting behavior change is crucial for the development of interventions that address difficult and costly health behaviors.