This new century will be an age in which humanity will strive for the recovery and preservation of a more natural environment and also for the establishment of clean and safe energy supply technologies. Up until now, environmental pollution and destruction on a global scale as well as the lack of sufficient clean energy have drawn great attention and concern to the vital need for totally new environmentally friendly, ecologically clean chemical technology, materials and processes -- the most important challenge facing chemical scientists for future generations. In this respect, zeolites offer very unique and interesting physicochemical properties such as a pore structure of a molecular scale, ion-exchange capabilities, a strong surface acidity and a unique internal surface topology. It would, therefore, be of great significance to develop well-defined molecular scale catalysts within zeolite cavities and frameworks which would lead to the design of more active and selective photofunctional and photocatalytic systems, particularly systems able to utilise the very abundant solar energy and convert them into safe and useful chemical energy. The central topics of this book is how to utilise photofunctional zeolites for applications in the recovery and preservation of our environment while, at the same time, trying to develop clean and safe energy supply technologies. A vital new era is emerging in the utilisation of the most limitless, clean and efficient energy source -- the sun by applying photofunctional materials. Research on photofunctional zeolites is only the beginning in the harvesting of this vast and powerful energy source not only to develop clean and safe photochemical processes and systems for industry but also to develop systems that can eliminate and cleanse the many devastating toxic agents that are polluting our environment.