This book is about the productive workplace. I am an environmental engineer for buildings and so I am concerned about perceptions based on data from the eyes, the ears, and the thermal sensors of the body. Human beings evolved in the world in a form that was adapted to the wide range of environments occurring naturally. Light levels vary from 0 to 100,000 lx, sound levels from very quiet to enough to break the eardrums, and temperatures characterised by ranges from, let us say, −40°C to +50°C. We have not adapted to meet the extremes of environment, but we are adapted to survive in the most common middle ground. We have developed buildings to relieve the stress caused by extreme environmental conditions and to extend the range of locations in the world where we can survive. We imagine that by reducing the environmental stress we can increase our ability to be productive.