International Naturist Federation (INF-FNI)

(From its website)

The International Naturist Federation is the only organisation representing naturism, nudism and non-sexual nude recreation worldwide.

Many countries have national naturist federations which bring together clubs, resorts and individual members within their countries. By being part of the INF-FNI, those federations offer their members the opportunity not just to be a member in the country concerned, but to be part of a much bigger global community – a worldwide Naturist family.