This publication contains proceedings of a Seminar on GLUCOSINOLATES IN RAPESEEDS – Analytical Aspects, held in Gembloux (Belgium) from 1 to 3 October 1986. The meeting was organized by request of the Commission of the European Communities in the context of the CEC Programme of Research on Plant Productivity. The main aim of the Seminar was to contribute to the elaboration of reliable quantitative methods for glucosinolate determination in rapeseeds. Fourty Experts from thirteen countries participated in this Seminar. Original contributions which were considered of special importance for the subject covered by the Seminar were presented and discussed. Thanks are due to the Chairmen, Dr. Heaney R., Dr. Biston R., Dr. Ri- baillier D., Prof. Dr. Robbelen G., authors and participants in the meeting for their contributions, friendliness and cooperation. Special thanks go to Dr. Mc Gregor (Canada) and Dr. Uppstrom B. (Swe- den) who gave Members the benefit of their knowledge. Finally, I would also like to thank those who have helped in organizing this Seminar Director Lecomte R. (Centre de Recherches Agronomiques de l’Etat, Gembloux), Rector Ledent A. (Faculte des Sciences Agronomiques de l’Etat, Gembloux), Prof. Severin M., Dr. Biston R., Mrs Bock and all my colleagues.