There are already ten police agencies using UAVs in law enforcement. A commercial market exists for supplying and training customers that will come from the over 18,000 law enforcement agencies in the USA.
Federal Emergency Management Agency (disaster area surveys and assessment, facilitate relief operations, communications relay).
Coast Guard (surveillance for counter narcotics, illegal aliens, illegal fishing, national security threats, search and rescue operations).
Department of Agriculture (pesticide & fertilizer spraying, insect sampling (bug catching), farm management).
National Aeronautics and Space Administration (high altitude atmospheric sampling, such as for ozone and pollution, astronomical sensing).
Forest Service (area surveillance of forest to determine plant growth and provide fire control, counter narcotics surveillance, mapping, firefighting with water or chemicals).
Weather Service (storm observation, tornado chaser).
Fish and Wildlife (river and estuary surveys for illegal hazardous waste dumps, wildlife tracking and accounting in remote areas, mapping, counter poaching, fishing law enforcement).
Department of Energy (monitoring nuclear facilities, reconnaissance for hazardous waste cleanup, atmospheric and climatic research).
Bureau of Land Management (archeological surveys and monitoring, hazardous waste dump surveys and monitoring).
State and Local Law Enforcement (riot control, area surveillance, highway patrol, counter narcotics surveillance, search and rescue).
State Department (area security surveillance).
Drug Enforcement Agency (counter narcotics surveillance).
Environmental Protection Agency (air sampling, hazardous waste dump surveys and monitoring).
Department of Transportation (traffic and highway surveys and monitoring, crash mitigation, mapping).
Engineers [civil missions] (monitoring recreational areas, surveying for dams, levees, and other construction projects, disaster control).
Communication Relay (equivalent to low-altitude satellites or cell towers).
Security (surveillance, counter-terrorism, detection of NBC & WMD).
Media (overhead cameras for news and special events).
Real Estate (pictures for selling property, surveying).
Surveying (city and suburban planning).
Farming and Ranching (check on cattle, fence lines, and work crews, spraying crops with pesticide and fertilizer, monitoring crops, soil, moisture, and pest conditions, and insect sampling).
Maritime (monitoring and reconnaissance of fishing areas, shipping hazards and disasters, and search and rescue).
Film Industry (aerial photography and special effects).
Archaeology (aerial observation of sites and digs).
Oil and Mineral Industry (gas and oil pipeline monitoring in desolate areas, search for mineral and fossil fuel deposits).
Railroads (aerial monitoring of rail lines and trains for operations and accidents).