The II. International Conference on Ion Beam Surface Layer Analysis was held on September 15-19, 1975 at the Nuclear Research Center, Karlsruhe, Germany. The date fell between two related con ferences: "Application of Ion-Beams to Materials" at Warwick, Eng land and "Atomic Collisions in Solids" at Amsterdam, the Nether lands. The first conference on Ion Beam Surface Layer Analysis was held at Yorktown Heights, New York, 1973. The major topic of that and the present conference was the material analysis with ion beams including backscattering and channeling, nuclear reactions and ion induced X-rays with emphasis on technical problems and no vel applications. The increasing interest in this field was docu mented by 7 invited papers and 85 contributions which were presen ted at the meeting in Karlsruhe to about 150 participants from 21 countries. The oral presentations were followed by parallel ses sions on "Fundamental Aspects", "Analytical Problems" and "Appli cations" encouraging detailed discussions on the topics of most current interest. Summaries of these sessions were presented by the discussion leaders to the whole conference. All invited and contributed papers are included in these proceedings; summaries of the discussion sessions will appear in a separate booklet and are availble from the editors. The application of ion beams to material analysis is now well established.