Bioenergy produced from biomass is increasingly used to substitute fossil energy sources. Trade of biomass is expected to increase in the following years due to disparities in production costs and potentials in countries and regions. In this paper the possibility of a certification scheme for minimizing negative socio-ecological impacts and for increasing a sustainable production of biomass is discussed, taking Brazilian bioethanol as an example. This case-study comes up with a first set of feasible sustainability standards for Brazilian bioethanol and discusses issues to be considered when developing sustainability standards. At the same time problematic aspects are identified. When incorporating opinions of different stakeholders, the setting of sustainability standards holds the inherent danger of being used as non-tariff trade barriers. This leads to the need for a regionalisation of sustainability standards and raises questions on structure and level of a certification scheme.