Describes a preventative treatment for bronze disease. The object is immersed in a solution of 3% by weight benzotriazole in alcohol, impregnated under vacuum, and dried. Objects thus treated remain stable up to 95% relative humidity. Benzotriazole forms a liaison with copper which is resistant to solvents, but unstable in acid conditions. For the last treatment the use of Incralac resin (paraloid B44 in toluene) is suggested. Incralac contains a small amount of benzotriazole which it is expected will migrate to the metal surface to perform its protective function when used as a coating for copper. The treatment can be adapted for archaeological excavations using a warm solution in order to stablize bronzes until ready for full conservation. Alternately, packaging materials may be impregnated by immersing in benzotriazole and thus used to enclose an object in benztriazole vapor.