Dynamics in confinement appears for many phenomena, starting from the clear case where atoms, molecules, liquids or solids are enclosed in 3-dimensional cavities of porous systems, over cases where atoms or molecules are restricted to move in 2D, like in the galleries of clays, in very thin films or at surfaces and finally to cases where confinement may have some but not the major influence on the dynamics, like for water confined in biological systems or copolymers, where soft polymer phases are surrounded by glassy polymer phases. Dynamics in confinement appears in a wide range of science, in chemistry, physics, biology and material science. Some of the fields have already considerable history, to mention only the reseach in zeolithes and its application in catalysis. Other fields have more recently emerged, e.g. the studies on extremely thin polymer films. A strong move into this field came recently from the scientific community investigating the liquid-glass transition, because it is hoped to solve the important open question of the existence of a correlation length by using porous matrices to impose a spatial restriction to the glass-forming liquid. Theories dealing with the dynamics in confinement compared to bulk are rarer, but many theoretical physicists or chemists are doing research by computer simulations and are tackling questions like relaxation behaviour of liquids in pores, the role of different wall types onto the polymer dynamics, the relaxation of polymer thin films, the existence of a length scale or the change of the glass transition in confinement. Experimentally, dynamics in confinement is probed by a large variety of techniques like calorimetry, dielectric, neutron, NMR, X-ray spectroscopy, etc., to mention only a few, and the results show that this manifold of techniques is needed and gives complementary information. This topical issue offers a selection of articles originating from presentations at the 2nd International Workshop on Dynamics in Confinement, held at the Institut Laue-Langevin (ILL) in Grenoble, France, January 22-25, 2003. The interest of the scientific community in this second workshop showed that the subject is timely and that the aim to bring experimental researcher and theorist working together in different scientific fields and with different experimental tools was successful. We want to take this occasion to thank the sponsors of this workshop: the ILL, the Neutron Round Table, the Institut de Recherche sur la Catalyse and the City of Grenoble, as well as the advisory board of the workshop who has helped to setup a very interesting programme.

Bernhard Frick , Michael Koza, and Reiner Zorn: Guest Editors