Meteorology is by nature a multidisciplinary and transnational subject and COST cooperation has proved to be a flexible and suitable framework at European level for meteorological activities such as the standardisation of observation techniques and harmonised transmission of meteorological data. Although meteorology is not covered by a specific Community programme as such, various Community actions dealing with meteorology are now included in the EEC research programme on climatology (the "EPOCH" programme - 1989-92) of mechanisms of extreme and sudden concerning particularly the study meteorological events, in order to predict catastrophies and consequently to reduce human and material losses. In the context of COST cooperation, which is supported by the Commission of the European Communities, the COST 73 project (1986-1991) associates 16 countries in Western Europe with the aim of setting up a weather radar network providing real-time measurements of rain, snow or hail precipitations. In this project, radar data are transmitted and combined if appropriate with satellite data - in one or more "compositing centres" of the participating countries, in order to improve weather forecasting. Together with the COST 73 Management Committee, the Commission of the European Communities organized a seminar on this matter, in Brussels on 5-8 September 1989, at the half-way stage of the project.