Biomethane (biogas) production is a waste-to-energy technology with outstanding climate, environmental and societal benefits. The aim of the present project is to improve the activities of a ubiquitous and important microbial group called ‘syntrophs,’ that work in tight cooperation to form methane in these biotechnology systems. Initially, cultivation, molecular and visualization approaches will be used to address key knowledge gaps within the area. This will enable us to reconstruct metabolic models to predict nutrient requirements and rationally design new culture conditions for these microbes. Thereafter, the outcome will be practically assessed in cultivation systems that mimic the habitat in large-scale facilities. The prospect is to contribute to the development of effective strategies to increase the methane forming capacity of syntrophs and by that improve productivity in biomethane production systems with decisive importance for the transition to a sustainable society.