Determining a visibility of an online conversation for a new participant includes presenting a user interface (UI) to a group of users to allow each of the users in the group of users to specify tags, the tags defining relationships between each of the users, determining initial participants from the group of users for an online conversation on a social network, identifying, based on the tags, a subject for the online conversation with respect to each of the initial participants of the online conversation, and determining, based on the subject, a visibility of the online conversation for a new participant from the group of users.