

Many variations of BDSM involve the voluntary relinquishment of control by one of the partners. The submissive partner surrenders control to the dominant in a ritualized interaction called a power exchange. Actions within a BDSM relationship take place over a period of time agreed upon by both parties, called a "game" or "scene." All parties involved usually derive pleasure from it, although many actions such as inflicting pain, humiliation or tying up would under normal circumstances be considered unpleasant. Sexual intercourse, whether oral, anal, or vaginal, may occur, but is not necessary.The fundamental principles for performing BDSM require that it be performed by mature and responsible partners, of their own free will and in a safe manner. Since the 80s, these principles have been summarized in the motto "Safe, sane and consensual".