In a stepped-care (SC) approach to treatment, more intensive interventions are implemented when less intensive interventions prove to be insufficient. It was hypothesized that a behavioral weight loss program with SC (BWLP+SC) would evidence superior treatment outcomes when compared with a BWLP without SC (BWLP).Forty-four obese, sedentary adults were randomly assigned to a BWLP+SC [i.e., problem-solving therapy (PST)] or a BWLP.Participants in the BWLP+SC lost significantly more weight and body fat, reported greater physical activity and greater improvements in diet, and were more likely to achieve their within-treatment weight loss goals than BWLP participants. Participants in the BWLP+SC who received PST (BWLP+SC [PST]) also evidenced superior treatment outcomes including superior weight loss maintenance (through 12 months posttreatment) compared with BWLP participants matched on SC eligibility [BWLP (SC matched)].BWLP+SC may improve treatment outcomes and participant motivation to achieve preestablished weight loss goals.