In consequence, the impacts shown here on land use and agricultural production abstract from the potential substitution among these input commodities which might alter the policy effects. In terms of biofuel policies, the increasing importance of sustainability criteria linked to support measures in many countries is not accounted for in the analysis. These tend to limit the choice of biofuels and their feedstock commodities that qualify for support (or for counting towards mandates), and may therefore alter the impact the support policies have on agricultural markets and incomes. An assessment of the direction and potential magnitude of these modifying effects is, however, beyond the scope of this analysis.