The term "BDSM" is an abbreviation derived from the terms bondage, discipline, dominance and submission, sadism and masochism. It defines a spectrum of behaviors, including dominance, submission, punishment, masochism, bondage, role play, and a large variety of other activities, frequently sexual in nature. "BDSM" is the collective term for a group of related sexual preferences common in issue-related literature, which are sometimes referred to as "D/s", "Sadomasochism", or "S&M" (also written "S-and-M").

BDSM can also be referred to as "kinky sex", "power exchange" or "the lifestyle", but each of these risks being confused with other alternative relationships or sexual behavior. Functionally, it is a form of 'power play', where power dynamics are used as part of the erotic experience. As such, BDSM mainly involves at least two participants, these being the "Top" who is the dominant partner in the relationship and the "Bottom" who is the submissive.

BDSM tends to involves "scenes" where the party enjoys a scenario which normally tends to involve one of the party voluntarily giving up control or authority. BDSM practitioners make a clear distinction between consensual BDSM and sexual abuse; it is important that the process is voluntary and that whoever is giving up control is willing to perform what tasks are asked of them. This is illustrated in the expression "Safe, sane and consensual", which means that the participants are aware of the dangerous nature of what they are doing, that what they are doing is sensible and in a right frame of mind, and that full informed consent has been given by everyone. A similar term used is "Risk-aware consensual kink" (RACK), although this practice expands the range of things that can be performed.