Since the publication of volume 3 in 1982 there has been a revival of research on magnetism and a pronounced increase in interest from both the scientific and the technological side. Volume 5 therefore contains chapters that provide the reader with an insight into modern trends in magnetism and new achievements in this area. The topics dealt with here include the increased activity and investigations of the magnetism of magnetic superconductors and investigations of the magnetic properties of hydrides, the understanding of first-order magnetic processes and of quadrupolar interactions in 4f systems and their role in magnetic ordering and magneto-elastic effects, and the magnetism of strongly enhanced itinerant alloys and compounds and the magnetism of Invar alloys.