In many traditions and statutes of civil or religious law, the consummation of a marriage, often called simply consummation, is the first act of sexual intercourse between two people, following their marriage to each other. The definition of consummation usually refers to penile-vaginal sexual penetration, but some religious doctrines hold that there is an additional requirement that no contraception must be used. In this sense, "a marriage is consummated only if the conjugal act performed deposits semen in the vagina".

Annulment is a legal procedure within secular and religious legal systems for declaring a marriage null and void. Unlike divorce, it is usually retroactive, meaning that an annulled marriage is considered to be invalid from the beginning almost as if it had never taken place. In legal terminology, an annulment makes a void marriage or a voidable marriage null.