The 1984 Advanced Study Institute on "Electronic Structure, Dynamics and Quantum Structural Properties of Condensed Matter" took place at the Corsendonk Conference Center, close to the City of Antwerpen, from July 16 till 27, 1984. This NATO Advanced Study Institute was motivated by the research in my Institute, where, in 1971, a project was started on "ab-initio" phonon calculations in Silicon. I~ is my pleasure to thank several instances and people who made this ASI possible. First of all, the sponsor of the Institute, the NATO Scientific Committee. Next, the co-sponsors: Agfa-Gevaert, Bell Telephone Mfg. Co. N.V., C & A, Esso Belgium*, CDC Belgium, Janssens Pharmaceutica, Kredietbank and the Scientific Office of the U.S. Army. Special thanks are due to Dr. P. Van Camp and Drs. H. Nachtegaele, who, over several months, prepared the practical aspects of the ASI with the secretarial help of Mrs. R.-M. Vandekerkhof. I also like to. thank Mrs. M. Cuyvers who prepared and organized the subject and material index and Mrs. H. Evans for typing-assist ance. I express particular gratitude to Mrs. F. Nedee, who, like in 1981 and 1982, has put the magnificent Corsendonk Conference Center at our disposal and to Mr. D. Van Der Brempt, Director of the Corsendonk Conference Center, for the efficient way in which he and his staff took care of the practical organization at the Conference Center.

The International Workshop on "The Use of Super computers in Theoretical Science" took place from July 30 till August 1, 1984, at the Conference Center of the "Priorij Corsendonk", close to the city of Antwerpen, Belgium. During the past decade computational science has developed itself to a third methodology besides the experimental and theoretical sciences. This remarkable evolution was only possible due to a drastic increase of the computational power of present day computers. Indeed, computational physics and chemistry as such is certainly not new, but it was only during the past ten years or so that realistic problems could be solved numerically to a sufficient degree of accuracy. During this workshop the state-of-the-art in high speed computation was presented by a team of lecturers who are well known for their competence in this field. It is a pleasure to thank several organizations and companies who made this workshop possible. First of all, the main sponsors: the Belgian National Science Found ation (NFWO-FNRS) and the "Universitaire Instelling Ant werpen". Next, the co-sponsors: Agfa-Gevaert N. V., Control Data Belgium and the Belgian Ministry of Education. Special thanks are due to Dr. P.E. Van Camp and Drs. H. Nachtegaele for the practical organization of this workshop. I would also like to thank Mrs. H. Evans for typing the manuscripts and for preparing the author and subject index. v Last but not least I express my gratitude to Mr.