This volume is the latest of the "Kirchberg-Proceedings". The previous 11 International Winterschools on Electronic Properties of Novel Materials, all held in Kirchberg, Austria, were devoted to conducting polymers, high temperature superconductors, fullerenes, and carbon nanotubes. Fullerenes and nanotubes are still in the center of interest, but the topic of the school and the proceedings is molecular nanostructures in general. The organizers have attempted to treat carbon nanostructures as a special case of molecular nanostructures, which also include silicon clusters, gold clusters,...