This case describes how the Maabjerg BioEnergy biogas plant was planned and constructed as a central part of a comprehensive industrial symbiosis near Holstebro in rural Jutland, Denmark. The case also describes how – and why, the subsequent plans to evolve the Maabjerg BioEnergy biogas based symbiosis into a more advanced industrial symbiosis in the Maabjerg BioEnergy Concept to this date have been unsuccessful. The story about Maabjerg BioEnergy and the Maabjerg BioEnergy Concept is a story about technical, economical and administrative challenges as well as a story about innovative technical, economical and administrative solutions. In addition, it is a story about a pioneering spirit developing and solidifying within the Danish bio-based economy, about the rise and fall of hopes and ambitions for fast development towards a green transportation sector, and about the slow and tiresome process of realizing new biorefinery concepts and symbiosis ideas and related markets and policies in Denmark and EU.