Abstract This paper explores the potential of combining technological innovation systems research with a participatory stakeholder dialogue, using empirical material from a dialogue on the options of sustainable biomass in the Netherlands and several historical studies into the emerging Dutch biomass innovation system. These studies identified and analysed functions (key processes) needed for the diffusion of this system. Using the functions as a heuristic to analyse and present this material, this paper shows that combining both approaches results in a richer understanding of the Dutch biomass innovation system. Where innovation systems research has not inquired in-depth into the normative dimensions of biomass innovation, the dialogue contributes to a better understanding of these. In contrast to systems research where the researcher defines system boundaries, the dialogue allowed system boundaries to be defined along the process in a bottom-up manner. This resulted in different ideas about challenges and opportunities. Where dialogue discussions were based on somewhat anecdotal information, biomass innovation systems research provided a historical and systemic contextualisation. Furthermore, the functions served as useful categories to explore future sustainable biomass options. We conclude that triangulation, using both historic and participatory methods, provides more insight, in terms of both range and depth, in the actual functioning of innovation systems and opportunities for improvement.