Affinity group

An affinity group is a small group of activists (usually from 5-20) who work together on direct action. It is a non-hierarchical group, usually made up of trusted friends and other like-minded people. It is a highly effective method of organization, as many actions may require a number of people working on it in different areas. Use of an affinity group also serves to keep information within the group (rather than, say, the police).

The use of affinity groups dates back to 19th century Spain, where they were called tertulias or grupos de afinidad by Spanish anarchists. They became popular again in the 1970s in the anti-nuclear movement in the United States. Today, the tool is used by many different activists: animal rights, environmental, anti-war, and anti-globalization, to name some examples.

A collection of affinity groups working together is called a cluster.