The Border Patrol and its parent organization, US Customs and Border Protection (CBP), have a variety of tools and techniques at their disposal that they use to guard the country's borders against smugglers, terrorists and undocumented aliens:

• Surveillance technology: Surveillance tools include infrared and night vision technology, gamma ray and x-ray imaging, radar, stationary cameras located along the borders and sensors that detect radiation and explosives to help identify terrorist weaponry. Since 2005, Predator unmanned aircraft have also been used to provide swift, wide surveillance coverage of areas that might be difficult for agents on the ground to reach.
• Dogs: The Border Patrol Canine Enforcement Program trains dogs -- primarily German Shepherds and Belgian Malinois -- to detect narcotics, unreported currency and smuggled humans and agriculture products at the country's ports of entry.
• Transportation: Border Patrol and other CBP agents must cover all sorts of environments and terrain, from land to sea to sky, so they use a range of vehicles in their work, including ATVs, snowmobiles, helicopters, boats, planes and even horses.
• Tips: The CBP has set up a telephone hotline (1-800-BE ALERT) for the anonymous reporting of suspicious activity.
• Physical evidence: Agents analyze physical evidence, studying human and vehicle tracks and utilizing tracking techniques used by Native Americans for centuries in order to locate illegal traffickers.
• Traffic stops: Agents stop and examine suspicious vehicles along the border, searching for smuggled immigrants and contraband.
• Fencing: The Secure Fence Act of 2006 called for the construction of 700 miles of fencing and other barriers. Although 300 miles of the fence was to be completed by the end of 2008, only about half of that amount was finished in that time frame. 
• ID Scanners: This modern technology allows agents to read chips in passports and IDs before drivers even get to a customs booth, allowing for quick identification of suspects and non-suspects alike.