ContentsIntroduction to European Gas Markets in Transition 1Andris Piebalgs and Marzia SesiniPART I SECURING SUPPLY TO EUROPE1 Rebuilding energy security 5Manfred Hafner and Pier Paolo Raimondi2 Filling the gaps in solidarity arrangements 27Marzia Sesini3 Security of supply in the regulatory and in the market designdiscourse 42Frank UmbachPART II DYNAMICS OF THE LIBERALISED NATURAL GASSECTOR IN THE EU4 Evolution of European natural gas market regulation 66Adrien Nicolle and Marzia Sesini5 Impact of the gas crisis on gas market regulation 81Anne-Sophie Corbeau6 Embracing decarbonization in the gas sector 102Andris PiebalgsPART III THE EVOLUTION OF THE NATURAL GAS VALUE CHAIN7 Transforming inside out: Opportunities for the upstreambusiness 114Andrea Stegher8 Network Codes and new challenges for midstream 123Sergio Ascari9 DSOs activities for a sustainable future 149Eva HennigPART IV ENERGY TRANSITION AND GAS SECTORDECARBONISATION10 Clean molecules for gas in the Fit for 55 165Anna Creti11 Market uptake of renewable gases 184Marzia Sesini and James Kneebone12 The long-term vision for the clean molecule economy 209Sylvia Elisabeth Beyer13 Conclusion to European Gas Markets in Transition 218Andreas C. Goldthau.