This volume describes modern developments in reflective, refractive and diffractive optics for short wavelength radiation. It also covers recent theoretical approaches to modelling and ray-tracing the x-ray and neutron optical systems. It is based on the joint research activities of specialists in x-ray and neutron optics, working together under the framework of the European Programme for Cooperation in Science and Technology (COST, Action P7) in the period 2002-2006.