The study consists of a Fitness Check on the Construction Sector in the policy areas of Internal Market and Energy Efficiency’. It aimed to assess the costs and benefits as well as the coherence of the EU legislation impacting on the construction sector. More specifically, it examined how various EU legal acts impact on the construction sector, and identified possible areas of improvement, including reduction of regulatory costs and burdens and a better alignment of provisions. The analysis included evaluating the efficiency, coherence, effectiveness, relevance and EU added value of most relevant provisions of EU legislation, with respect to the objective for a more competitive and sustainable construction sector, in particular for small and medium enterprises. A particular attention was paid therein to identify any synergy or inefficiency arising from these acts. The Study adopts a retrospective view, covering the effects of EU legislation over the 2004 – 2014 period. The analysis covered nine pieces of current legislation as well as their predecessors in force during the relevant period. The Study focuses primarily on the ‘core’ construction sector, i.e. the construction and renovation of buildings and specialized construction activities. In order to provide a comprehensive picture of the effects of EU legislation, the Study also covers the other sectors in the construction value chain, i.e. the manufacture of construction products construction-related professional services, e.g. architects, engineers, or energy auditors, and real estate. The Study consists of two components, namely an economic analysis, concerned with the identification and, whenever feasible, the quantification of the costs and benefits of EU legislation; and a legal analysis, aimed at assessing the coherence of EU legislation, with the identification of shortcomings, overlaps, gaps, and obsolete measures. Fact finding work involved the review of a variety of documentary sources as well as primary data collection from firms, stakeholders, and public authorities.