The objective of this paper is to give a comprehensive review of initiatives on biomass certification from different viewpoints of stakeholders, including national governments (such as The Netherlands, the UK, Belgium and Germany), the EC, NGOs, companies, and international bodies up until October 2007. Furthermore, opportunities and restrictions in the development of biomass certification are described, including international trade law limitations, lack of adequate methodologies, stakeholder involvement requirements and certification costs. Next, five different approaches for the implementation of a biomass certification system are compared and discussed. Main differences are the voluntary or mandatory character and the geographical extent of the proposed strategies in terms of biomass end-use. It is concluded that criteria to ensure the sustainable production of biomass are needed urgently. To some extent criteria categories can be covered using existing systems, but others (such as GHG and energy balances, changing land-use) require the development of new methodologies. A gradual development of certification systems with learning (through pilot studies and research) and expansion over time, linked to the development of advanced methodologies can provide valuable experience, and further improve the feasibility and reliability of biomass certification systems. However, better international coordination between initiatives is required to improve coherence and efficiency in the development of sustainable biomass certification systems, to avoid the proliferation of standards and to provide a clearer direction in the approach to be taken. Finally, next to certification, alternative policy tools should be considered as well to ensure sustainable biomass production. (c) 2008 Elsevier Ltd. All rights reserved.