The article discusses transition dynamics towards a Danish low-carbon society based on studies of energy production and consumption. This article shows how the Arena of Development and policy mix approaches may inform the analysis of system transition to a low carbon society. The Arena of Development approach is an actor-centred approach that focuses on how path dependencies of socio-technical systems may be challenged when controversies and matters-of-concern produce ‘arenas’ where established governance configurations and policies of a socio-technical system are challenged. Re-organising actor-constellations are constitutional for arenas and define their boundaries and the policies employed. We discuss the historic transitions in relation to four focal areas of Danish attempts to become independent of fossil energy: wind-power integration in the energy system, energy savings, biomass and sustainable mobility. The analysis demonstrates the conflicts and mixes of policy measures that have moved transition processes forward, but sometimes also stalling them. The analysis shows how changing controversies, arena configurations and policy mixes move forward the energy transition process.