This book records contributions presented at the Third Session of the EIFAC (European Inland Fisheries Advisory Commission of the Food and Agriculture Organization of the United Nations) and OlE (Office International des Epizooties) Cooperative Programme of Research on Aquaculture (COPRAQ) Fish Diseases. The session was held at the In­ stitute for Zoology and Hydrobiology, Veterinary Faculty, Munich, on the 23-26 October 1979. Sponsorship of the session was by the Federal Ministry of Food Agriculture and Forest of the Federal Republic of Gennany and by the Deutsche Forschungsgemeinschaft (DFG). The EIFAC was represented by Prof. Dr. N. Fijan, Zagreb, Yugosla­ via, and the OlE was represented by Prof. Dr. P. Ghittino, Turin, Italy and Dr. P. de Kinkelin, Thiverval-Grignon, France. The Third COPRAQ Session brought to Munich an array of scien­ tists from allover the world. Over 100 participants from more than 20 countries (most were from Europe, but Australia, Canada, Egypt, Israel, Kuweit, Nepal, and USA were also represented) discussed the major problems affecting the health of cultured fish. 30 papers for the slide sections and 13 papers for the poster section were submitted. Topics included were viral, bacterial, and parasitic diseases of fish, as well as emerging problems and approaches in aquaculture.