Ecotourism, bioprospecting and non-timber product marketing have been promoted recently as market-based instruments for environmental protection, but without sound understanding of the resulting net conservation effects. We present evidence on the local effects of recent argan oil commercialization in Morocco, a seemingly promising case of conservation through resource commercialization. We find that resource commercialization creates mixed net conservation incentives because assumptions implicit in the prevailing logic prove incorrect. The experience of southwestern Morocco provides a cautionary tale about conservation strategies founded on resource commercialization, emphasizing that the biology of a resource often exerts greater influence on conservation outcomes than do market forces.