The fruit flies of mango and guava are the main constrain of production, marketing and exports of these lovable desserts. In Sudan the aggravation of this problem in the last decade pushed the Sudan Government to consider these flies as national pests to which the sharp decline in exports referred. However, this work geared a variety of preharvest and postharvest treatments to combat these notorious insects. These treatments include spraying of soft insecticide cypemethrin and entomopathogenic funi, the latter also sprayed in guava besides a neem seed powder suspension. Moreover, the postharvest treatments tested include hot water, hot dry air, hot humid air, gamma irradiation, some fruit characteristics, harvest time and storage as well. All these treatments significantly reduce the fly infestation and only few can completely disinfest the fruits. However, some other studies are also included in this book which drew and drawing a lot of attention of the experts worldwide.