Extramarital sex

Extramarital sex is sexual activity by a married person with someone other than their spouse. It may occur with or without a spouse’s knowledge or consent.

Adultery: Adultery is voluntary sexual relations in which at least one participant is married to someone else. Many legal and religious traditions use this term for extramarital sex, though definitions vary.
Relationship satisfaction: Relationship satisfaction is a person's overall evaluation of the quality and fulfillment of a romantic partnership. Discovering extramarital sex can alter how spouses assess their marriage.
Consensual non-monogamy: Consensual non-monogamy is a relationship arrangement in which all involved agree that romantic or sexual relationships may include multiple partners. It permits outside relationships without the secrecy that often defines infidelity.
Marriage: Marriage is a socially or legally recognized union that establishes rights and obligations between spouses. Extramarital sex is defined in relation to marriage and its expectations.
National Opinion Research Center: The National Opinion Research Center is a social science research organization at the University of Chicago. Its General Social Survey has measured reported extramarital sex in the United States.
Infidelity: Infidelity is a breach of relationship agreements involving romantic, sexual, or emotional involvement outside a partnership. It is the broader relationship concept that can include extramarital sex.
Betrayal trauma: Betrayal trauma is psychological distress arising when a trusted person violates an important relationship expectation. Some spouses experience discovery as a profound breach of trust.
Polyamory: Polyamory is the practice of having or seeking multiple romantic relationships with the knowledge and consent of everyone involved. It shows how multiple partnerships can be openly negotiated rather than concealed.
Canon law: Canon law is the ecclesiastical law governing the institutions and members of a Christian church. Christian legal traditions developed rules addressing adultery and marital obligations.
General Social Survey: The General Social Survey is a nationally representative survey of social attitudes and behaviors in the United States. Its repeated questions support comparisons of self-reported adultery across time.

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