Energy certification schemes for buildings emerged in the early 1990s as an essential method for improving energy efficiency, minimising energy consumption and enabling greater transparency with regards to the use of energy in buildings. However, from the beginning their definition and implementation process were diffuse and, occasionally, have confused building sector stakeholders. A multiplicity of terms and concepts such as energy performance, energy efficiency, energy ratings, benchmarking, labelling, etc., have emerged with sometimes overlapping meanings. This has frequently led to misleading interpretations by regulatory bodies, energy agencies and final consumers. This paper analyses the origin and the historic development of energy certification schemes in buildings along with the definition and scope of a building energy certificate and critical aspects of its implementation. Concepts such as benchmarking tools, energy ratings and energy labelling are clarified within the wider topic of certification schemes. Finally, a seven steps process is proposed as a guide for implementing building energy certification. (C) 2008 Elsevier B.V. All rights reserved