This paper qualitatively examines how members of a large private Facebook group view the risks of information disclosure to their privacy and the strategies they employ to navigate and manage those risks. The paper adds to an emerging interest in how privacy is managed collectively and within dynamic large groups, thus moving beyond established knowledge of privacy management on individual and small-scale levels. The work builds on semi-structured interviews with 20 members of a private Facebook group and draws on Communication Privacy Management theory. The study shows how privacy management practices are enacted at individual, intragroup, and group levels. Findings show that participants associate very high risks with sharing private information in the group, partly because it consists of a mix of known others and strangers, who are potentially geographically co-located. They adopt several strategies for managing and protecting their privacy at all three levels. The risks associated with context, time, and spatial collapse of the imagined audience are identified as important to how participants experience information disclosure in the group. The paper concludes by identifying some practical implications that serve as a call for developers to design privacy tools that support dynamic groups’ privacy challenges and needs.