The importance of developing new, clean and renewable sources of energy will continue to grow in the foreseeable future and so will the need for the education of researchers in this field of research. The interest and challenges of the field continue to shift from simple homogeneous solutions to increasingly more complex heterogeneous systems and interfaces. Over the past decade there have been numerous theoretical and experimental breakthroughs many of which still exist only in the primary literature. The aim of this book is to gather in one volume the description of modern, sometimes exploratory, experimental and theoretical techniques applied to the dynamics of interfacial electron and electronic excitation transfer processes studied in the context of solar energy conversion. The intended treatment will be fundamental in nature and thus applicable to a broad range of hybrid photovoltaic and photocatalytic materials and interfaces. The book will focus on the dynamic aspects of the electron injection, exciton and carrier relaxation processes, as well as coherence effects, which continue to provide the impetus and the greatest challenge for the development of new methodologies.