Description Surface Alloys and Alloy Surfaces is concerned with the structural, compositional, electronic and chemical properties of the surfaces of solids in which the surface layers, at least are alloyed. Two different categories of system are covered - the surfaces of bulk alloys (alloy surfaces) and surface phases in which one or more outermost atomic layers are alloyed, while the underlying bulk involves no such intermixing (surface alloys). Importance of Topic The surfaces of bulk alloys have long been known to be of practical interest for their chemical properties. It has also long been known that the surface composition of such alloys commonly differs from that of the underlying bulk. However, our understanding of these chemical and physical phenomena is far from complete and the application of surface science methods to investigate these phenomena is a manifestation of a general trend to study the surfaces of increasing complexity. Surface alloy formation, as a much more recently recognized phenomenon deserves more attention. Why This Title This title is important as it provides new insights into a mixture of new and old problems. It is the first to cover the important mixture of material on surface alloys and alloy surfaces. Each chapter is written by experts in different areas of these two interrelated topics, covering theory and experiment, physics and chemistry, geometrical and electronic structure. The coverage of the surface alloy topic is especially novel as it is relatively newly-recognised as quite a common phenomenon.