Military support comes from all components of the Department of Defense. It includes Title 10 forces, which are active duty and reserve forces; Title 32, the National Guard; and logistical support through four regional offices. A number of major commands are involved. Reconnaissance operations are the most frequently requested form of support, and border areas are observed in a variety of ways. These include staffed observation posts, the use of trained recon elements with night-vision devices and long-range optics, remotely monitored sensors, ground surveillance radar operations, and aerial reconnaissance. Intelligence analysis is another useful aspect of military assistance. Engineer support and military transportation are also useful. However, military personnel do not perform the law enforcement functions of search, seizure, or arrest. Another legal constraint is the prohibition of active duty and reserve entry onto private land without written permission of the owner. Mexican sensitivity to United States military efforts is another issue. Overall, military support will continue to be important. Photograph and 9 reference notes