The Conway Hall Ethical Society, formerly the South Place Ethical Society, based in London at Conway Hall, is thought to be the oldest surviving freethought organisation in the world and is the only remaining ethical society in the United Kingdom. It now advocates secular humanism and is a member of Humanists International.

The Ethical movement is an ethical, educational, and religious movement established in 1877 by the academic Felix Adler (1851–1933). In an effort to develop humanist codes of behavior, the Ethical movement emerged from the moral traditions of the secular societies of Europe and the secular society of the 19th-century United States. In practice, the Ethical movement organized themselves as two types of organization: (i) a secular humanist movement and (ii) a predominantly moral movement with a religious approach.