Abstract: Various embodiments facilitate proximity-based social networking. In one embodiment, a Proximity-based Social Networking facilitator system (“PSN”) determines and provides a user with relevant information based on his proximity to other users of his social and other networks. Proximity determinations may be based on various factors, including user location, user affinity, user activities, and the like. In one embodiment, the PSN determines a group of users that are proximately located to one another, and provides users of the group with information about other users without disclosing their actual location on a map. The users of the group receive the information via mobile computing devices, and can use the mobile computing devices to further interact with the other users of the group, such as by arranging meetings, communicating, and/or engaging in transactions.