This case study describes the Enough Abuse Campaign, a multidisciplinary, statewide effort to prevent child sexual abuse in Massachusetts. The study uses the Institute of Medicine's Framework for Collaborative Community Action on Health to provide a systematic description of the campaign's process of implementation, which includes: (a) developing a state-level infrastructure for child sexual abuse prevention, (b) assessing child sexual abuse perceptions and public opinion, (c) developing local infrastructures in three communities and implementing training programs focused on preventing perpetration of child sexual abuse, (d) facilitating changes in local communities to child-sexual-abuse-related systems, and (e) inviting Massachusetts residents to join an advocacy-based movement to prevent child sexual abuse. This case study concludes with future directions for the campaign and topics for future research related to child sexual abuse. (Contains 1 figure.)