This paper provides an assessment of the economic impact at the farm level of agricultural biotechnology on global agriculture. It examines the economic impacts on yields, key costs of production, direct farm income, indirect (non-pecuniary) farm level income effects and impacts on the production base of the four main crops of soybeans, corn, cotton and canola. The analysis shows that there have been substantial net economic benefits at the farm level amounting to $10.8 billion in 2009 and $64.7 billion for the 14-year period (in nominal terms). The non-pecuniary benefits associated with the use of the technology have also had a positive impact on adoption (in the USA accounting for the equivalent of 23% of the total direct farm income benefit). Biotech crops have also made important contributions to increasing global production levels of the four main crops; adding, for example, 83 million tonnes and 130 million tonnes, respectively, to global production of soybeans and corn.