A mundane but theoretically interesting and practically relevant situation presents itself on social networking sites: the co-presence of multiple groups important to an individual. This primarily qualitative study concentrates on the point of view of individual SNS users and their perspectives on multiple group affiliations. After charting the perceived multiplicity of groups on the social networking site Facebook, we investigated the relevance of multiple groups to the users and the effect of group co-presence on psychological identification processes. Users deal with group co-presence by managing the situation to prevent anticipated conflictive and identity-threatening situations. Their behavioral strategies consist of dividing the platform into separate spaces, using suitable channels of communication, and performing selfcensorship. Mental strategies include both the creation of more inclusive in-group identities and the reciprocity of trusting other users and being responsible. I...