Introduction The U.S.-Mexican border, la frontera, is far more than a line or markers or fences that separate two countries. It is history and commerce and culture, as well as a minefield of po liti cal tension, fear, vio lence, and exploitation. It is binational coop- eration as well as competition. Along its winding path of nearly 2,000 miles from the Pacific Ocean to the Gulf of Mexico, it is a landscape of desert and waterway that has been traversed for centuries and coveted by many. But most of all the border is its people, great numbers of whom, carrying their required legal documents, cross each day: the Mexican commercial truck driver in Nuevo Laredo who begins his work day at about 8 a.m. and typically returns home around 11 p.m. after crossing the border several times through long processing and customs lines the young woman student from Juárez, Chihuahua, who crosses the border to go to school at the University of Texas-El Paso the elderly woman who manages to secure a ride from Tucson, Arizona, to cross the border in Nogales where she can fill a medical prescription at far less cost than she can in the United States the couple from Brownsville, Texas, who cross the Gateway Bridge to have lunch at Garcia’s, a popu lar restaurant and bar in Matamoros, Tamaulipas the Mex- ican American auto mechanic who lives in Ciudad Acuña, Coahuila, because he can afford a house there and crosses the river to work in Del Rio, Texas the man from San Luis Río, Colorado, who wakes up most mornings at 4 a.m., walks down- town to the parking lot near Del Sol supermarket where buses await to take him and many other workers across the border, and then boards another bus that takes him to lettuce fields near Yuma, Arizona, where he often works for ten hours before making the return trip home the man from Douglas, Arizona, who crosses the border to volunteer at the Migrant Resource Center in Agua Prieta, Sonora, to help recently deported men, women, and children with basic needs such as food and medical attention, as well as advice on how to reach their next destinations. At border ports of entry across four states, over 350 million crossings occur each year. But through the years, and especially into the twenty- first century, the image of the border has taken on an increasingly sinister image. If the border can be seen as a metaphor for cross-cultural and bilingual melding, it is also a source of grow- ing anxiety over national security and safety. The life of the border and its sister cities involves a long history of conflict and interaction and evolving interrelationships between people and cultures. For over a century and a half, the U.S.-Mexican border has been the scene of violence, racial