A bill signed by President Bush includes a significant increase in funding for border security. Over the years, successive administrations have tried to tighten control of the border with Mexico. Fences and patrols have changed immigration routes, but so far, nothing has stopped people coming across.
Caitlin Harrington, covers Homeland Security for Congressional Quarterly
Doug Mosier, public information officer for the El Paso Border Patrol
Clare May, police chief of the border town of Columbus, N.M.