​Energy efficiency contributes to the main objectives of energy policy in the European Union: energy security, cost effectiveness and environmental benefits. However, the efficiency potential remains widely untapped. Will White Certificate Instruments, a new framework instrument to foster end-use energy efficiency, help to close the energy efficiency gap? The analysis compares the political process of choosing and designing White Certificate Instruments in Italy, France and Great Britain. The book shows that the type of policy instrument as well as its image has an influence not only on agenda-setting but also on the policy instrument’s effectiveness due to interactions with existing energy efficiency discourses, regulatory traditions and the prevailing policy style.