Limitation of space allows only a selection of papers to be listed. Foreword. Acknowledgements. Conclusions. Opening Session. Opening remarks (A. van Alphen, Chairman Steering Committee Acidification Research). Atmospheric Deposition. Trace Gases. Long term measurement of SO2 dry deposition over vegetation and soil comparisons with models (D. Fowler et al.). The use of the gradient method to monitor trace gas fluxes over forest: flux-profile functions for ozone and heat (J. Duyzer, H. Weststrate). Ammonia / Ammonium. Ammonia and ammonium in the atmosphere: present knowledge and recommendations for further research (W.A.H. Asman). Measurement and modelling of ammonia exchange over arable surfaces (M.A. Sutton et al.). Particle Deposition. Deposition of aerosol to coniferous forest (G.P. Wyers et al.). Microscopic processes governing the deposition of trace gases and particles to vegetation surfaces (J. Burkhardt). Generalization; Total Atmospheric Deposition and Soil Loads; Measurements and Models. On the determination of total deposition to remote areas (B.B. Hicks). Quantifying the scale dependence in estimates of wet and dry deposition and the implications for critical load exceedances (R.I. Smith, D. Fowler, K.R. Bull). Effects of Acid Deposition on Forest Ecosystems in The Netherlands. Effects of Acid Deposition on Forest Ecosystems in The Netherlands. Large scale impacts of acid deposition on forests and forest soils in The Netherlands. Ecological effects of atmospheric deposition on non-forest ecosystems in Western Europe (R. Bobbink, J.G.M. Roelofs). Future of Acidification Research. Today's Knowledge; Is It Sufficient for Tomorrow's Decision Making Purposes? Lessons learned in acidification research: Implications for future environmental research and assessments (E. Cowling). Reliability of environmental information obtained by modelling and monitoring (J.A. Hoekstra et al.). Future Research; Combination with Other Environmental Topics. Future of acidification research (T. Paces). Acidification and metal mobilization : effects of land use changes on Cd mobility (P.F. Romkens, W. de Vries). Posters. Critical Loads / Exceedances. Setting critical loads of acidity for dystrophic peat - a new approach (E.J. Wilson et al.). A comparison of models for the assessment of critical loads on different scales of observation (R.J.M. lenz, S. Mendler, R. Stary). wet Deposition / Throughfall. Eight years studying bulk and wet deposition in Spanish Basque country (D. Encinas, H. Casado). Scavenging of gases during growth of ice crystals (G. Santachiara, F. Prodi, F. Vivarelli). Dry Deposition / Concentrations. Dry depositions of acidifying and alkaline particles to forests: model and experimental results compares (W. Ruijgrok). Fine resolution modelling of ammonia dry deposition in Great Britain (R.J. Singles, M.A. Sutton, K.J. Weston). Miscellaneous.Carbon partitioning in Douglas-fir (E.G. Steingrover, M. Posma, W.W.P. Jans). The characteristics of acid precipitation in Southern China (T. Bai, X. Tang). List of Participants.