 301 terrestrial mammal species are threatened with extinction due to bushmeat hunting, deforestation, agricultural expansion, human encroachment, and competition with livestock in developing countries, which could lead to the loss of vital ecological and socioeconomic services. A multi-pronged conservation strategy is proposed to save these mammals from immediate extinction and avoid a collapse of food security for hundreds of millions of people. This article was authored by William J. Ripple, Catherine Abernethy, Matthew G. Betts, and others.