The creation of molecular materials that have desired electrical conductance and magnetic properties demands the precise arrangement of molecules in the solid state. Such controlled arrangement has been achieved very elegantly by supramolecular chemists, especially those practising crystal engineering. Presenting articles by foremost experts in crystal engineering, molecular conductors and magnetic magnetism, this text reveals the results of an interdisciplinary union that may well have a profound influence on the future of materials science. Theoretical studies reveal potential areas of interest for those investigating molecular conductors and magnets, as well as materials that exhibit both properties. A survey of the state-of-the-art should appeal to all those doing research in supramolecular chemistry and materials science.