1. Subtask A: user perspectives and requirements

2. Subtask B: integration and optimisation of daylighting systems

3. Subtask C: daylighting design tools

4. Subtask D: daylight performance tracking network and design support

References

Daylight is today a topic of growing interest to designers and building owners worldwide. This interest is driven by concerns for the quality of the indoor environment as well as by international efforts to reduce building energy use. While the daylighting of buildings has been an architectural design strategy for hundreds of years it has only been in the last few decades that architects, engineers, researchers, and manufacturers have tried to extend its use to provide reliable and persistent energy savings. Over time it has become apparent that this requires an understanding of both the technical challenges of developing integrated daylighting systems as well as the occupants' reaction to daylit spaces and their use of lighting and shading controls. This understanding has been recently enhanced through an international research project developed by and managed through the Solar Heating and Cooling Programme of the International Energy Agency (IEA). IEA SHC Task 31, ˇ®Daylighting Buildings in the 21st Century', lasted from September 2000 to June 2006 and involved institutions from thirteen countries in Europe, North America, Asia, Australia and New Zealand. Many of the papers presented in this special issue were written by participants of Task 31 so that their scientific findings can be made available to researchers and practitioners worldwide. This research communication provides an overview of these research activities as well as other research and technology transfer activities that were ongoing when this special issue went to press.

• lighting, daylighting