Based on ethnographic fieldwork that included participant observation of a grassroots organization in New York City during 1999-2000 and the tracing of Mexican immigrant youths' psychological development through societal and individual histories, this study documents how Mexican children and youth experience, understand, and discuss their illegal presence in America, the kinds of violence to which they are exposed and their response to it. The study concludes that U.S. institutions of power and policy, along with the media, foster a popular conception of undocumented immigrants as law-breakers and as threats to the socioeconomic quality of the country. This view of undocumented immigrants encourages both physical and psychological violence against them, which in turn precipitate violent behaviors by these children and youth. The organization examined in this study was Asociacion Tepeyac, a grassroots organization committed to defending the legal and human rights of Mexican immigrants in New York City. All members are volunteers who are primarily undocumented Mexican immigrants. Such community-based organizations can structure collaborative projects between families and schools so as to inform each other about common problems their children face and to design violence prevention programs that are culturally meaningful. Also, teacher education programs should include curricula that prepare educators to recognize the special needs of students from immigrant populations. Mexican families continue to settle permanently in the United States in spite of their undocumented status, so it is in the best interest of all communities to collaborate in preventing physical and psychological violence against and perpetrated by these young immigrants. 29 references