FUDOSI or FUDOESI (French: Fédération Universelle des Ordres et Sociétés Initiatiques, Latin: Federatio Universalis Dirigens Ordines Societatesque Initiationis) was a federation of autonomous esoteric or mystical orders and societies, founded on August 14, 1934, in Brussels, Belgium, and disbanded in 1951. It was opposed by the similarly named Fédération Universelle des Ordres, Fraternités et Sociétés Initiatiques (FUDOFSI).