The General Diamond Workers' Association of Belgium (Dutch: Algemene Diamantbewerkersbond van België, ADB; French: Syndicat des Ouvriers Diamantaires) was a trade union representing workers in the diamond trade in Belgium.
The union was founded on 19 August 1895, as the Antwerp Diamond Workers' Association.
[1] The union set up the Universal Alliance of Diamond Workers in 1905, and shared its headquarters with this small international trade secretariat.
After the war, the industry entered a gradual decline, and the union focused on maintaining pay and conditions.
It affiliated to the General Federation of Belgian Labour, and membership peaked in 1955 at 12,304, then declined to only 2,694 by 1992.