Total power exchange

In BDSM, Master/slave or M/s is a relationship in which one individual serves another in an authority-exchange structured relationship. Unlike Dominant/submissive structures found in BDSM in which love is often the core value, service and obedience are often the core values in Master/slave structures. The participants may be of any gender or sexual orientation. The relationship uses the term "slave" because of the association of the term with ownership rights of a master to their slave's body, as property or chattel. While male "masters" will usually be referred to as "Master", whether or not female Masters are referred to as "Master" or "Mistress" may depend upon whether they identify as following the "Leather" or BDSM path.

The Master/slave (or owner/property) relationship is entered into on a consensual basis, without the legal force of historical or modern non-consensual slavery, that is forbidden by the laws of most countries.

Outside the BDSM community, the relationship of Master/slave is sometimes regarded as a form of consensual sexual slavery. In BDSM, a slave is a specific type of submissive. The Master/slave relationship refers to the relationship between the individuals involved, and does not necessarily require any specific acts, sexual or otherwise, though sexual activity is usually an aspect of the relationship. The sexual aspect could be conventional, and not necessarily BDSM. A slave could also be a masochist or bottom, but this is not always the case.

Some participants regard the relationship as sexual roleplay, while others enter into the relationship on the basis of a highly committed, long-term, submissive lifestyle.

Various forms of symbolism are sometimes used to affirm the owner/slave relationship. These include wearing the owner's collar, being registered in a slave register, adopting (sometimes legally changing to) a name chosen by the owner, or engaging in a public declaration or ritualized ceremony of some type.

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Wikipedia