Defense Agencies

ACC
Air Combat Command
AFSPC
Air Force Space Command
BMDO
Ballistic Missile Defense Organization
DEFENSE
Defense Department
DISA
Defense Information Systems Agency
DRMS
Defense Reutilization and Marketing Service
DTIC
Defense Technical Information Center
JCS
Joint Chiefs of Staff
NAWCWPNS
Naval Air Warfare Center Weapons Division

Intelligence Agencies

CIA
Central Intelligence Agency
DIA
Defense Intelligence Agency
NSA
National Security Agency
SS 
Secret Service
USCSOI 
U.S. Customs Service Office of Investigation

Law Enforcement

ATF
Bureau of Bureau of Alcohol, Tobacco and Firearms
BOP
Federal Bureau of Prisons
CID
U.S. Army Criminal Investigation Command
COURTS
U.S. Federal Courts
DEA
Drug Enforcement Administration
FBI
Federal Bureau of Investigation
FINCEN
Financial Crimes Enforcement Network
FLETC
Federal Law Enforcement Training Center
MARSHALS
U.S. Marshals Service
NIJ
National Institute of Justice

Military Branches

NatGuard
National Guards
USA
United States Army
USAF
United States Air Force
USCG
United States Coast Guard
USMC
United States Marine Corps
USN
United States Navy

All Branches of The Military
Find A Military Base, Any Branch

Government Agencies

BLS
Bureau of Labor Statistics
BOT
Bureau of Transportation
CDC
Centers for Disease Control and Prevention
CENSUS
U.S. Department of Commerce Bureau of the Census
CONGRESS
U.S. House of Representatives
CUSTOMS
U.S. Customs Service
DOE
U.S. Department of Education
DOE
U.S. Department of Energy
DOT
Department of Transportation
EEOC
Equal Employment Opportunity Commission
EXECUTIVE
The White House
FDIC
Federal Deposit Insurance Corporation
FEC
Federal Election Commission
FEMA
Federal Emergency Management Agency
FHWA
Federal Highway Administration
FMS
Financial Management Service
FTC
Federal Trade Commission
GAO
Government Accounting Office
GPO
U.S. Government Printing Office
GSA
U.S. General Services Administration
HHS
U.S. Dept of Health & Human Service
IRS
Internal Revenue Service
JUSTICE
Justice Department
NARA
National Archives and Records Administration
NASA
National Aeronautics and Space Administration
NCDC
National Climatic Data Center
NIMH
National Institute of Mental Health
NOAA
National Oceanic & Atmospheric Administration
NSF
National Science Foundation
NTIS
National Technical Information Service
OSHA
Occupational Safety & Health Admin.
SBA
Small Business Administration
SEL
Space Environment Laboratory
SSA
Social Security Administration
STATE
State Department
TREASURY
Treasury Department
USCODE
U.S. Internet Law Library U.S. Code

National Organizations

ABA
American Banker's Assoc.
ABA
American Bar Assoc.
ABEA
American Bail Enforcement Assoc.
ACA
American Collectors Association
ACFE
Assoc. of Certified Fraud Examiners
ACI
Assoc. of Christian Investigators
AIIP
Assoc. Independent Information Professionals
APISP
Assoc. of Professional Investigators and Security Providers
AMIA
American Medical Investigators Assoc.
ASIS
American Society for Industrial Security
IOA
Investigators of America
IRE
Investigative Reporters and Editors
LPIN 
Licensed Private Investigator Network
NACM
National Assoc. of Credit Management
NALI
National Assoc. of Legal Investigators
NAIS
National Assoc. of Investigative Specialists
NAPPS
National Assoc. of Professional Process Servers
NCISS
National Council of Investigators & Security Svcs
NCSEA  
National Child Support Enforcement Assoc.
NFPA
National Federation of Paralegal Assoc.
NLCA
National Livestock Contractors Assoc.
WIA
Women Investigators Assoc.
WSATI
Western States Auto Theft Investigations

Regulator Agencies

EPA
U.S. Enviroment Protection Agency