Reports on recent research in the UK and Europe on the integration of atrium and conservatory spaces into commercial buildings. Summarises the design strategies that led to energy-efficient solutions and considers cost issues. Compares the results of the study with a number of projects completed since 1970, with and without atria, and comments on the effectiveness of the design strategies employed on the basis of operational experience.KEYWORDS: Atria, commercial, buildings, case studies, designing, estimating, UK, Europe, performance, costs, comfort.