The Miridae, or plant bugs, with more than 1,300 genera and 11,130 described species, represent the largest and most diverse family of Heteroptera. Although many plant bugs are phytophagous and may cause serious damage to crops, a great many are predatory and may be important in biological control programs. In the Neotropics, about 561 genera and more than 3,400 species are included in seven of the world's eight recognized subfamilies. In this chapter, we give an overview of the classifi cation, general life history, and economic importance and provide identifi cation keys to the Neotropical subfamilies and tribes. For each subfamily, we present a brief diagnosis, an overview of the respective tribes and subtribes, and key literature.