Lygusspp. and their parasites were surveyed on alfalfa, cotton, grain sorghum, guayule, and a number of weed hosts in southern Arizona.Lygus hesperusKnight,L. elisusVan Duzee, andL. desertinusKnight were found at Yuma, while these species andL. lineolaris(Palisot de Beauvais) were found in other areas.L. hesperuswas the predominant species found, although others predominated on individual plant species. The mymaridAnaphes ovijentatus(Crosby&Leonard), a parasite of eggs, was the most common parasite found, with monthly averages of up to 100% parasitization.Leiophron uniformis(Gahan), a braconid parasite of the nymphs, was found in all areas surveyed, but was much less abundant thanA. ovijentatus.The tachinidAlophorellasp. emerged in small numbers from adults collected at Tucson and Benson.