Superconductivity is a phenomenon occurring in certain materials generally at very low temperatures, characterised by exactly zero electrical resistance and the exclusion of the interior magnetic field. Like ferromagnetism and atomic spectral lines, superconductivity is a quantum mechanical phenomenon. It cannot be understood simply as the idealisation of "perfect conductivity" in classical physics. Furthermore, superconductivity occurs in a wide variety of materials, including simple elements like tin and aluminium, various metallic alloys and some heavily-doped semiconductors. It does not occur in noble metals like gold and silver, nor in pure samples of ferromagnetic metals. This book gathers the latest research from around the globe in this dynamic field and highlights topics such as super-conducting miniundulators, super-conducting transitions in wire networks, the orbital physics of superconductors, the super-conducting circuits of Josephson junctions, and the types of stresses that affect super-conducting properties and behaviour.