Defence Assistance Organisation

The Defence Assistance Organisation (Bulgarian: Организация за съдействие на отбраната, ОСО), initially the Voluntary Defence Assistance Organisation (Bulgarian: Доброволна организация за съдействие на отбраната, ДОСО) was a government-sponsored network of youth clubs in the People's Republic of Bulgaria. It was created in 1947 as the People's Union of Sports and Technics, a government-sponsored body where Bulgarian youth could voluntarily engage in activities that were in some form related to the Bulgarian People's Army.

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