Phthalocyanines exhibit intriguing physic-chemical properties that render them important as a class of molecular functional materials. In addition to their tra- tional industrial applications as dyes and pigments, more recently their use as the organic semiconductors,photodynamictherapy medicines, non-linear optical ma- rials, catalysts for the photo oxidation, optical recording materials, and gas sensors attracts great research interests in these tetrapyrrole species. As manifested by the rapidly increasing number of related scienti?c publications in recent years, great progress has been made in the ?eld of advanced phthalocyaninematerials. Tremendous efforts have been paid toward the development of new phtha- cyanine molecular materials as well as toward their applications. Recent emphasis in both academic researches and technical ?eld has been put on the design and synthesis of novel phthalocyanine species, the structure–propertyrelationship, se- assembly properties, molecular electronics and opto-electronics, and dye-sensitized solarcells.Althoughexcellentreviewsandmonographsaboutphthalocyanineswere publishedseveralyearsago,it is time to providea surveyof a numberof newimp- tant developments in this fascinating area of phthalocyanine chemistry. The aim of this book is to bring both the academic and industrial researchers an easy way to the new progress of phthalocyanines made lately in related ?eld.