This volume contains selected papers presented at the 42nd Biennial Meeting (Hauptversammlung) of the Kolloid-Gesellschaft held at the RWTH Aachen University September 26-28, 2005. The meeting's emphasis was given to "Smart Materials: Foams, Gels and Microcapsules" but also provided a general overview on current aspects of colloid and polymer science in fundamental research and applications. The contributions in this volume are representative of the diversity of research topics in colloid and polymer science. They cover a broad field including the investigation of synthesis and properties of advanced temperature sensitive particles and their biomedical applications, drug delivery systems, foams, capsules, vesicles and gels, polyelectrolytes, nanoparticles surfactants and hybrid materials.