"Electrochemisty at Metal and Semiconductor Electrodes" covers the structure of the electrical double layer and charge transfer reactions across the electrode/electrolyte interface. The purpose of the book is to integrate modern electro chemistry and semiconductor physics, thereby, providing a quantitative basis for understanding electro chemistry at metal and semiconductor electrodes. Electrons and ions are the principal particles which play the main role in electro chemistry. This text, therefore, emphasizes the energy level concepts of electrons and ions rather than the phenomenological thermodynamic and kinetic concepts on which most of the classical electro chemistry texts are based. This rationalization of the phenomenological concepts in terms of the physics of semiconductors should enable readers to develop more atomistic and quantitative insights into processes that occur at electrodes. The book incorporates many traditional disciplines of science and engineering such as inter facial chemistry, biochemistry, enzyme chemistry, membrane chemistry, metallurgy, modification of solid interfaces, and materials' corrosion. The text is intended to serve as an introduction for the study of advanced electro chemistry at electrodes and is aimed towards graduates and senior undergraduates studying materials and inter facial chemistry or those beginning research work in the inter facial of inter facial chemistry.