Myzus persicae (Sulzer) (Hemiptera: Aphididae) is a key pest in Italian peach orchards but also in many herbaceous crops. Insecticide treatments selected resistant populations. Several resistance mechanisms in M. persicae are known: esterases and mixed function oxydases overproduction and target site insensitivity for carbamates, pyrethroids and also for cyclodienic insecticides. More recently a highly specific target site resistance mechanisms have been found against neonicotinoid insecticides. These resistance mechanisms allow aphids to survive when spayed with traditional aphicides. In Italy resistant strains are widely distributed but they are more frequent where agriculture is more intense. Management strategies are discussed.