Abstract: This is a time of enormous investment in new health-care buildings. The UK plans to create upwards of a hundred hospitals and thousands of primary-care clinics and surgery centres. In the USA, more than $200 billion will be spent on new hospitals over the next decade. This wave of construction provides an opportunity to create better buildings by use of the emerging science of evidence-based design, in which the design process is guided by an empirical understanding of the effects of health-care physical environments on safety, efficiency, and clinical outcomes.