[en] The NATO/CCMS Workshop on open-quotes Risk Assessment for Accidental Pollution Related to the Maritime Transport of Harmful Substancesclose quotes which took place at CEDRE in 1991 was a follow-up to the workshops which took place in 1987 and 1989. It was the direct continuation of work accomplished during the first two seminars and covered the following topics: Improvement and Intercomparison of Models: elaboration of the list of indispensable parameters for modeling slick movements analysis and integration of the physico-chemical processes studied at sea. Model Validation: release of bulk chemicals drift of drums and containers of toxic substances. Risk Assessment for Man and the Environment: development and adaptation of Help-in-Decision-Making System (ex: CAMEO, MORGANE, etc.) means for rapid, on-site detection (including the advanced Canadian know how in this domains). Intervention Ways and Means: experience of a rescue company; research for elements for Help-in-Decision-Making regarding the location and eventual recovery of drums and containers lost at sea