Although individual differences are known to influence numerous aspects of social perception, such as person memory and individuation, little is known about how such variations may affect social categorization. Extending prior research, the present study tested one potential moderator: familiarity with group members. Specifically, straight participants (n = 84) reported their real-life experiences with gay men and categorized faces as gay or straight. Results showed that participants who reported greater familiarity with gay men were significantly more sensitive, or accurate, in judging the sexual orientations of men from their faces. These results are discussed in terms of their theoretical implications for social perception and future research directions are outlined. (C) 2013 Elsevier Ltd. All rights reserved.