Body dissatisfaction is associated with numerous health consequences and is pervasive among college women. Effective interventions exist that reduce body dissatisfaction in college women by helping them resist sociocultural pressures to conform to the appearance ideal, such as the Body Project. Yet research is limited on whether social and behavioral processes help participants reduce their engagement in sociocultural appearance-ideal messages and contribute to the intervention's effectiveness. The primary purpose of the present study was to examine these social and behavioral processes, including the changes in college women's social networks associated with their participation in the Body Project. Undergraduate and graduate students participated in the two session, peer-led version of the Body Project and completed measures at five timepoints (Baseline 1, Baseline 2, Post-intervention, 1-month Follow-up, 3-month Follow-up). The measures assessed constructs examined previously in Body Project research in addition to body dissatisfaction maintenance behaviors (appearance comparison tendency, body checking, and negative body talk) and participants' perceived social networks' body dissatisfaction and related behaviors. Seventy-nine completed Baseline 1, of which 39 completed at least one Body Project session and 31 completed the full two-session intervention. Because of the coronavirus pandemic, Body Project groups were stopped indefinitely and 22 who completed Baseline 1 were unable to attend their pre-scheduled group. Latent growth models with three piecewise slopes (assessment effects, intervention effects, and maintenance effects) were used to examine changes in these measures beyond the effects of time. Significant intervention effects were found for the previously measured constructs and the body dissatisfaction maintenance behaviors examined. One marginally significant change in participants' social networks was found; the friends participants removed from their social networks engaged in more disordered eating than the friends they added at 1-month follow-up. Despite this limited evidence for social network change, the study revealed several ways in which social networks may perpetuate body dissatisfaction and related behaviors. This was one of the first studies to examine these social and behavioral processes within the Body Project and assess these constructs in women's social networks. Findings suggest that additional processes, including reductions in body dissatisfaction maintenance behaviors and the facilitation of perceived group similarity and closeness contribute to the intervention's effectiveness and should be explored further in future research and considered in the development of cost-effective intervention modifications. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]