Activities and relationships within a BDSM context are often characterized by the participants taking on complementary, but unequal roles; thus, the idea of informed consent of both the partners becomes essential.
The terms "submissive" and "dominant" are often used to distinguish these roles: the dominant partner ("dom") takes psychological control over the submissive ("sub").
Whether it is a public "playspace"—ranging from a party at an established community dungeon to a hosted play "zone" at a nightclub or social event—the parameters of allowance can vary.
Some have a policy of panties/nipple tape for women (underwear for men) and some allow full nudity with explicit sexual interaction allowed.
Explicit sexual activity, such as sexual penetration, may occur within a session, but is not essential.
Such explicit sexual interaction is, for legal reasons, seen only rarely in public play spaces, and it is sometimes specifically banned by the rules of a party or playspace.
They further argue that setting a discrete line between "safe" and "not-safe" activities ideologically denies consenting adults the right to evaluate risks vs rewards for themselves; that some adults will be drawn to certain activities regardless of the risk; and that BDSM play—particularly higher-risk play or edgeplay—should be treated with the same regard as extreme sports, with both respect and the demand that practitioners educate themselves and practice the higher-risk activities to decrease risk.