Intended both for a basic undergraduate course and as a reference work for graduates and researchers, this book covers two fundamental aspects of electrochemistry: electrochemistry in solution and interfacial electrochemistry. By bringing these two subjects together into a single volume, the author clearly establishes the links between the physical foundation and the analytical applications of electrochemistry. The philosophy of this book has been to publish all the mathematical derivations in detail, allowing the reader to follow the calculations that lead to the main results. With this rigorous approach, the author has provided a book of reference constructed from first principles.