The UK Kink GuideEvidence-led glossaryAn umbrella for relationship structures in which adults knowingly agree that more than one sexual and/or romantic connection may occur.
Manual claim and limitation notes are shown where an individual source audit is complete. Other evidence-type labels are a publisher aid awaiting source-by-source confirmation.
Consent & relationships
Illustration created using generative AI; not documentary evidence.
In brief
Consensual non-monogamy, or CNM, includes varied arrangements such as polyamory, open relationships and swinging. Its defining feature is informed agreement rather than the number of partners alone. It differs from concealed infidelity because relevant partners know the relationship is non-exclusive.
Each person consents to their own participation and agreements. One partner cannot consent on behalf of another person, and being in CNM does not mean being available to everyone.
Disclosure agreements should be clear about timing and privacy. Transparency between partners does not authorise sharing another person's intimate details without permission.
The broad umbrella for knowingly agreed non-exclusive sexual and/or romantic structures.
CNM commonly allowing multiple loving or emotionally intimate relationships.
A partnered arrangement permitting defined outside sexual or romantic connections.
A breach of an agreement; it can occur in monogamous and non-monogamous relationships.
Topics may include time, safer sex, disclosure, hosting, finances, public visibility and changing feelings. Agreements work best when they are understandable, realistic and open to review.
Rules imposed through fear or unequal leverage may not reflect genuine agreement. Ending or renegotiating remains available.
Reviews generally find similar average psychological wellbeing and relationship quality in CNM and monogamous groups. A recent meta-analysis found no overall satisfaction advantage for either structure.
CNM people may face stigma in families, workplaces and healthcare. These pressures can affect wellbeing independently of relationship functioning.
Partner number alone does not determine STI risk. Testing, barriers, vaccination, activities and communication provide more useful information.
UK relationship recognition, parental rights, housing and benefits may privilege couples or marriage. Personal legal questions require specialist advice.
Non-graphic examples
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