This volume will present the reader with an update on the scientific research on organic chemistry of nitroso compounds that was performed in the last two decades. The overview will include the original synthetic applications of nitroso compounds, but will also cover the discovery of novel physico-chemical phenomena and their potential future uses. The properties that form the basis for this technological potential originate from the intriguing property of C-nitroso molecules to form dimers through the formation of a relatively weak nitrogen-nitrogen double bond. The equilibrium between the different monomeric and dimeric forms, which appears under controlled environmental parameters, opened new areas of research in organic chemistry. The novel paradigm presented in this volume includes insight into the original problem of organic reactivity and synthesis, but also sheds light on the solid-state reaction mechanisms. A number of fascinating photochemical, electrochemical, supramolecular, and biological properties, as well as advanced techniques in spectroscopy, now enables us to use these compounds as molecular models for studying a number of general chemical concepts. .