Social sorting refers to the discriminatory effects of surveillance, and particularly to the ways in which large-scale practices of observation and monitoring facilitate profiling and screening of social groups. The term social sorting was coined and developed by David Lyon in response to what he identified as the increasingly totalizing nature of surveillance, particularly evidenced by heightened security measures and racial discrimination in the immediate wake of the attacks on September 11, 2001. Social sorting generally refers to practices of discrimination and filtering enabled by new technologies. Such sorting is an ethically ambiguous practice: Even when functional, its benefits, risks, and further social implications must be considered.