Abstract: | Objective: This investigation was designed to improve behavioral weight loss program (BWLP) treatment outcomes by providing stepped care (SC) to individuals experiencing difficulties with weight loss during treatment. SC entails transition to more intensive treatments when less intensive treatments fail to meet treatment goals. In a BWLP, motivational interviewing (MI) may increase participants' motivation toward behavioral change and thus complement the acquisition of behavioral change skills. It was hypothesized that BWLP + SC (MI) participants (i.e., participants who failed to meet weight loss goals and received MI) would demonstrate superior treatment outcomes when compared with BWLP (SC matched) participants (i.e., participants who failed to meet weight loss goals but did not receive MI). Design: Fifty-five obese, sedentary adults were randomly assigned to a BWLP + SC or a BWLP. Main outcome measures: Changes in weight, cardiorespiratory fitness, self-reported physical activity, and diet (i.e., calories, percentage daily intake of fat, protein, and carbohydrates) in response to treatment were assessed. Results: Participants significantly decreased their weight, increased physical activity/fitness, and improved dietary intake (ps |