This book is an introduction to the basic concepts of artificial photosynthesis. Artificial photosynthesis is about learning from nature ¿Stealing nature¿s secrets¿. Many of the concepts that will explore in this book require an understanding of basic concepts of physical chemistry, including kinetics, electrochemistry, spectroscopy, supramolecular & laser chemistry. In the first part of this book, the concept of natural photosynthesis and semi-artificial systems were briefly described. This is followed by the details of artificial photosynthesis and examples of the recently reported photosynthetic molecular & supramolecular systems in order to mimic functions of the antenna-reaction center of the natural process. The relations between structures & photoinduced reactivities of the reported artificial photosynthetic donor-acceptor systems are discussed in relation to the efficiency of the intramolecular electron-transfer/energy-transfer processes by utilizing the laser photolysis technique & other complementary techniques. Finally, the photocatalytic production of hydrogen peroxide as a more promising solar fuel than hydrogen is discussed in relation with the natural photosynthesis.