This paper examines relations between the state and capital in Argentina with respect to agricultural biotechnology. Argentina is one of the world's leading exporters of genetically modified (GM) crops and is a key player in the global politics of biotechnology. Whereas in other parts of the world, including other countries in Latin America, active civil societies and some governments have rejected the technology, Argentina has adopted it as a central accumulation strategy. The desirability of this strategy has been secured in material, institutional and discursive arenas of power, producing a particular expression of ‘bio-hegemony’. Looking at the role of business in the political economy of agricultural biotechnology is revealing both of the extent and forms of corporate power and contributes to an understanding of hegemony in practice.