From 1891 to 1914, Madagascar was producing forest rubber for export to Europe. Although Madagascar's contribution to the world rubber market was very modest, this episode had major consequences for the island's ecology. Many endemic species were exploited, with a view to maximising short-term productivity with no consideration for sustainability. This was one of the first cases of biological resource exploitation in Madagascar for industrial purposes, and was one of the factors that triggered awareness of the value of Madagascar's biodiversity and the threats to which it might be exposed because of badly managed human activities. Highly repressive legislation was introduced and imposed on the local populations, who were considered mostly to blame for these threats. However, naturalists considered these policies to be ineffective and responded in deliberately alarmist terms designed to provoke a reaction from allegedly over-lenient policy- makers. Their position was caught on the wrong foot in 1942-45, when the war effort revitalised Malagasy rubber production. Nevertheless, the episode was one of the factors behind the creation, in 1927, of a network of protected areas managed by naturalists, making Madagascar a conservation pioneer in Africa. Meanwhile, efforts were made to promote the domestication and/or introduction of high-potential rubber species. With the emergence of Asian rubber production, however, all attempts at rubber cultivation in Madagascar were abandoned, thus sparing Madagascar's forests from further destruction. This episode shows how Malagasy rubber species survived not thanks to naturalist discourse, the creation of protected areas or the enforcement of repressive legislation, but because an unprofitable sector was abandoned for reasons of economic realism.