Hormesis is the application of potentially harmful agents at low doses to living organisms in order to induce stress responses. When fruit are exposed to low doses of UV a number of changes are induced including the production of anti-fungal compounds and delays in ripening. Both of these responses could be exploited by the horticultural sector to reduce postharvest losses. We review the results of UV treatment of a variety of fruits and the work done in identifying chemical changes in them. The prospects for treating fruits with UV on a commercial scale are considered.