Whether it's on application forms (which currently still only have two check boxes for sex and none for gender), arts groups that rely on single-sex membership or sex-segregated teams, the inclusion of transgender individuals may provide a challenge. In the area of athletics, sports sociologist Eric Anderson, author of the upcoming book In the Game: Sport, Homophobia, and the Gay Male Athlete, says, \"Transgender athletes present a real threat to both the way we do sport, and the way those who control sport think about issues of sex and gender.\"