This research programme is fully funded by Citrus Research International, with emphasis on the sustainable management of important preharvest diseases, and pre- and postharvest insect pests of citrus in South Africa. The increased pressure on South African agriculture from the EU Green Deal, particularly on export crops such as citrus, necessitates the need to focus research on gaining a better understanding of the epidemiology of diseases and biology of insect pests in order to develop and advise on effective Integrated Pest Management strategies. The diseases currently under consideration in this programme are Phytophthora root rot, Botrytis grey mould and Alternaria brown spot. The complex of fruit flies (Bactrocera and Ceratitis species) and psyllids present or at risk of introduction to South Africa are the focus of our entomological research.