Examples are disclosed herein that relate to constraining communication among HMD devices. One example provides a computing system comprising a logic machine and a storage machine holding instructions. The instructions are executable to receive, for each of a plurality of head-mounted display devices, vantage point data, determine, for each of the plurality of head-mounted display devices, whether one or more other head-mounted display devices are within a vantage point scope of that head-mounted display device, the vantage point scope being based on the vantage point data of that head-mounted display device, and constrain, for each of one or more head-mounted display devices, delivery of communication data from that head-mounted display device to one or more of the plurality of head-mounted display devices, such constraint based on whether that head-mounted display device is within the vantage point scope of one or more of the plurality of head-mounted display devices.