Considerable progress in energy efficiency in the building sector is reported in the majority of the UNECE member States, and still reaching the potential often falls short due to flawed policy frameworks, and lack of public awareness on available modern technologies and education on long-term economic and social benefits of energy efficiency improvement. This publication is prepared in response to the outlined challenges and aims to elucidate the status of implementation of energy efficiency standards in buildings and deployment of appropriate technologies, and to identify good policy practices and replicable solutions. It also proposes a set of general recommendations and priority actions arising from the analysis.