This report summarises a wealth of information on the building design features that are known to have positive impacts on the health, wellbeing and productivity of office workers. Teams of experts from the around the world were assembled to investigate a range of office design factors, from indoor air quality, thermal comfort and daylighting, to acoustics, interior layout, views and biophilia. The impacts of location and amenities were also considered. The findings show, overwhelmingly, that the design of an office can have a material impact on the health, wellbeing and productivity of its occupants. This report also provides a unique, high-level framework to enable building owners/occupiers to measure the impact their building has on employee health, wellbeing and productivity in order to use that information in financial decision-making. Includes lots of non-technical advice and guidance checklists at the back of the paper.