This volume brings together some of the presently available theoretical techniques which will be useful in the design of solid-state materials. At present, it is impossible to specify the atomic composition of a material and its macroscopic physical properties. However, the future possibilities for such a science are being laid today. This is coming about due to the development of fast, cheap computers which will be able to undertake the calculations which are necessary.Since this field of science is fairly new, it is not yet quite clear which direction of analysis will eventually prove to be the most successful. In this respect the author has included the most relevant promising subject areas, based on seven years of research experience in the field. An extensive literature already exists for most of the areas covered here, thus when more detailed analysis can be found elsewhere, the assumptions made are discussed, and only an outline of the method involved is presented. Comprehensive indexes are provided to assist the reader in further studies. This is a potentially important field which is slowly getting underway and only needs a significant development to attract a broader scientific interest. The work will be of considerable interest to program managers needing to assess this new field.