Ethical non-monogamy (ENM) is a practice of non-monogamous intimate or sexual relationships that are distinguished from infidelity by the knowledge and consent of those involved, and from polygamy by the various partners not being in a single marriage. ENM is a subset of consensual non-monogamy (CNM), which includes swinging, polyamory, open relationships, cuckquean fetishism, and cuckolding fetishism. In an ENM relationship, everyone involved must consent to the relationship structure, and the focus is on consent, honesty, and openness. Unlike cheating, ENM is a collaborative decision, and the people involved in a relationship make agreements about what the relationship dynamic will look like. ENM can take many different forms, depending on the needs and preferences of the individuals involved in specific relationships. Some common forms of ENM include polyamory, open relationships, and swinging.