The current study tested a psychosocial interactive model of perfectionism, self-efficacy, and weight/shape concern within a sample of women with clinically significant bulimic symptoms, examining how different dimensions of perfectionism operated in the model. Individuals with bulimia nervosa (full diagnostic criteria or subthreshold) completed measures of bulimic symptoms, multidimensional perfectionism, self-efficacy, and weight/shape concern. Among those who were actively binge eating (n=180), weight/shape concern was associated with binge eating frequency in the context of high perfectionism (either maladaptive or adaptive) and low self-efficacy. Among those who were actively vomiting (n=169), weight/shape concern was associated with vomiting frequency only in the context of high adaptive perfectionism and low self-efficacy. These findings provide support for the value of this psychosocial interactive model among actively binge eating and purging samples and for the importance of considering different dimensions of perfectionism in research and treatment related to bulimia nervosa.