Sexual play involving pain and power dynamics have been documented since the third and fourth centuries and the practice has many names including bondage and discipline and sadism and masochism (BDSM), domination and submission (D/s), sadism and masochism (SM), fetish or kink. BDSM and fetish professionals may play the role of a dominant, submissive or switch (a person who plays both roles). Both men and women (including transgender men and women) may work as professional dominants, submissives or switches. Within the industry professional dominants are often referred to as “pro doms” which can include men (Masters) or women (Mistresses). Respectively, professional submissives and switches are referred to as either “pro subs” or “pro switches”