Dr. Dale Tiller has a doctorate in Experimental Psychology from the University of Oxford, U.K. From 1988 – 1999, he was Leader of the Lighting Group at the National Research Council of Canada Institute for Research in Construction. Dr. Tiller chairs the CIE Technical Committee on Post-Occupancy Evaluation; until recently he was the chair of the Illuminating Engineering Society of North America (IESNA) Psychological Aspects of Lighting Committee. He also serves on several other technical committees of the IESNA and CIE. From 1997 – 1999, Dr. Tiller was IESNA Regional Vice President for Canada. His research interests include: psychological aspects of lighting and energy conservation in buildings.