"Since September 11, 2001, the need to secure U.S. borders has increased in importance and attracted greater public and Congressional attention. The Department of Homeland Security (DHS) has spent billions of dollars to prevent the illegal entry of individuals and contraband between ports of entry--government designated locations where DHS inspects persons and goods to determine whether they may be lawfully admitted into the country. Yet, while DHS apprehends hundreds of thousands of such individuals each year, several hundreds of thousands more enter the country illegally and undetected. U.S. Customs and Border Protection (CBP), a component of DHS, is the lead federal agency in charge of securing our nation's borders. This testimony summarizes GAO's [Government Accountability Office] work on DHS's efforts on selected border security operations and programs related to (1) inspecting travelers at U.S. ports of entry, (2) detecting individuals attempting to enter the country illegally between ports of entry, and (3) screening of international travelers before they arrive at U.S. ports and challenges remaining in these areas. GAO's observations are based on products issued from May 2006 through February 2008. In prior reports, GAO recommended various actions to DHS to, among other things, help address weaknesses in the traveler inspection programs and processes. DHS has generally agreed with our recommendations and has taken various actions to address them."