International Workers' Olympiads were an international sporting event arranged between 1925 and 1937 by Socialist Workers' Sport International (SASI). It was an organisation supported by social democratic parties and International Federation of Trade Unions. Workers' Olympiads were an alternate event for the Olympic Games. The participants were members of various labor sports associations and came mostly from Europe. Nowadays the CSIT World Sports Games are the successor sports events of the International Workers' Olympiads. The "World Sports Games" is the main highlight and a new brand of the International Workers and Amateurs in Sports Confederation (CSIT). It is a sports event for thousands of workers and amateurs held every two years. The CSIT is an international multi-sports organization.

Socialist Workers' Sport International was an international socialist sporting organisation, based in Lucerne. It was founded in 1920, and consisted of six national federations at the time of its foundation. Initially it was known as International Association for Sports and Physical Culture. Informally it was known as the Lucerne Sport International. It adopted the name SASI in 1926. The Austro-Marxist Julius Deutsch was the president of SASI.