The articles in this book summarize the work presented at the mid-term workshop of the COST (European Cooperation in the Fields of Scientific and Technical Research) action on Nanostructured Materials, which was held in October 2001 in Limerick, Ireland. The collection gives an excellent overview of the state-of-the-art, topical research areas in this field, and the progress made by the coordinated research projects. The articles cover synthesis, physical properties and characterization of nanostructured materials, such as magnetic and ferroelectric nanoparticles, nanoparticles in biological systems, metallic nanoparticles, nanocomposites, particle-reinforced polymers, semiconductor nanoparticles and thin films.