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A-Z index of U.S. government departments and agencies

Find contact information for U.S. federal government departments and agencies including websites, emails, phone numbers, addresses, and more.



The Tax Court decides disputes between the Internal Revenue Service and taxpayers.


Tax Court

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The Taxpayer Advocacy Panel is a volunteer organization that works to improve the customer service of the Internal Revenue Service (IRS) by collecting the comments and recommendations of taxpayers and bringing their concerns to the attention of the IRS.

The Tennessee Valley Authority provides low-cost electricity in seven southeastern states, and provides flood control, navigation, and land management for the Tennessee River system.

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The United States Trade and Development Agency links U.S. businesses to export opportunities by funding project planning activities, pilot projects, and reverse trade missions.

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The U.S. Trade Representative negotiates with foreign governments to craft trade agreements and resolve disputes.

The Department of Transportation is responsible for planning and coordinating federal transportation projects. It also sets safety regulations for all major modes of transportation.

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The Transportation Security Administration (TSA) protects the nation's transportation systems to ensure freedom of movement for people and commerce.

The Bureau of Transportation Statistics collects and publishes comprehensive transportation statistics.

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The Department of the Treasury manages Federal finances by collecting taxes and paying bills and by managing currency, government accounts and public debt. The Department of the Treasury also enforces finance and tax laws.

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The Trustee Program protects the integrity of the Federal bankruptcy system. The Program monitors the conduct of bankruptcy parties and private estate trustees. It also identifies and helps investigate bankruptcy fraud and abuse.

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