Two major challenges facing the FAO/IAEA Division of Nuclear Techniques in Food and Agriculture are to increase or sustain food production and to achieve this with minimal undesirable effects on the environment. This word is being carried out against a background where population growth has outstripped food production in many developing countries. Critics of pesticide technology are concerned about possible effects on the quality of food, and the impact on the environment. This symposium addressed the second of these concerns, and was intended to provide an opportunity to share views on the current situation and to develop recommendations on what needs to be done in future.