These volumes contain the invited and contributed talks of the first general Conference of the Condensed Matter Division of the European Physical Society, which took place at the campus of the University of Antwerpen (Universitaire Instelling Antwerpen) from April 9 till 11, 1980. The invited talks give a broad perspective of the current state in Europe of research in condensed matter physics. New developments and advances in experiments as well as theory are reported for 28 topics. Some of these developments, such as the recent stabilization of mono-atomic hydrogen, with the challenging prospect of Bose condensation, can be considered as major break throughs in condensed matter physics. Of the 65 invited lecturers, 54 have submitted a manuscript. The remaining talks are published as abstracts. The contents of this first volume consists of 9 plenary papers. Among the topics treated in these papers are: - electronic structure computations of iron the density functional theory hydrogen in amorphous Si topologically disordered materials nuclear antiferromagnetism stabilization of mono-atomic hydrogen gas covalent and metallic glasses nonlinear excitations in ferroelectrics.