A Quality Assurance (QA) system taking the overall supply chain of solid biofuels into account is essential for an increased trade and use of these energy carriers. A methodological approach is necessary which ensures-besides an efficient control of the single processes considered throughout the overall chain-also the control over the overall supply chain by an adequate integration of previous and subsequent process steps controlled different organisational units. Such a QA-system needs to provide tools to demonstrate that the level of quality demanded by customers is achieved and that their confidence in biofuels is enhanced. Against this background this paper shows the characteristics of solid biofuels with respect to the necessary supply chain and the need for a Quality Management (QM) system with emphasis on QA and Quality Control (QC). Furthermore, a step-by-step methodology is presented which helps operators running the overall or parts of the supply chain to implement and to apply an appropriate QM-system. Additionally important terms and customer requirements are explained. The system described is compliant with the requirements of the Technical Specification CEN/TS 15234 Fuel quality assurance elaborated by CEN/TC 335. (c) 2006 Elsevier Ltd. All rights reserved.