Section headings and selected papers: Foreword. Conclusions and recommendations of the conference. The Quality of the Danube Waters and Trends of Changes in the Light of Recent Investigations. Estimation of the readily oxidizable organic matter reserve and its effect on the intensity of bacterial destruction in the Danube river, I Kh Bashmacova. Studies on the contamination status of the Danube river basin waters, measures of protection, and rational exploitation of the water resources, D V Jankovic. Qualitative and quantitative analyses of heavy metals in the Danube at the profile situated at the village of Vinca, A Marjanovic. Influence of Hydraulic Engineering Works in the Basin and in the River on Water Quality and Sedimentation. Downstream effects of intermittent power generation, G Bretschko & O Moog. N;trient input and trophic status of the 'Neue Donau', a high-water control system along the River Danube in Vienna, Austria, M T Dokulil & G A Janau;r. Modeling changes in the water quality of the Sava River caused by impounding water at the Vrhovo hydroelectric power plant, U Krajnc & M Rismal.; Thermal and Radioactive Pollution of the Danube and its Tributaries. Water quality of River Sava at inflow of a pulp and paper mill effluent, V V Cibulic. The impact of the Chernobyl accident on the radioactivity of the River Danube, Lj Conkic et al . Experiences and Measures of Water Quality Control. The Vienna sewerage system, P Bortenschlager. Risk management of accidental water pollution: an illustrative application, J Pinter et al . Subject index.