Introduction of same-sex marriage laws has varied by jurisdiction, being variously accomplished through a legislative change to marriage laws, a court ruling based on constitutional guarantees of equality, or by direct popular vote (via a ballot initiative or a referendum).

The recognition of same-sex marriage is a political, social, human rights and civil rights issue, as well as a religious issue in many nations and around the world, and debates continue to arise over whether same-sex couples should be allowed marriage, be required to hold a different status (a civil union), or be denied recognition of such rights. Allowing same-gender couples to legally marry is considered to be one of the most important of all LGBT rights.

Allowing same-gender couples to legally marry is considered to be one of the most important of all LGBT rights.