The following description of Executive Order is from the U.S. Department of State:

President Bush signed Executive Order 13224 on September 23, 2001.  Executive Order 13224 gives the U.S. Government a powerful tool to impede terrorist funding and is part of our national commitment to lead the international effort to bring a halt to the evil of terrorist activity.  …  In issuing Executive Order 13224, President Bush declared a national emergency to deal with the unusual and extraordinary threat to the national security, foreign policy, and economy of the United States posed by grave acts of terrorism and threats of terrorism committed by foreign terrorists, including the terrorist attacks in New York and Pennsylvania, and on the Pentagon committed on September 11, 2001, and the continuing and immediate threat of further attacks on U.S. nationals or the United States.

In general terms, the Order provides a means by which to disrupt the financial support network for terrorists and terrorist organizations by authorizing the U.S. government to designate and block the assets of foreign individuals and entities that commit, or pose a significant risk of committing, acts of terrorism.  In addition, because of the pervasiveness and expansiveness of the financial foundations of foreign terrorists, the order authorizes the U.S. government to block the assets of individuals and entities that provide support, services, or assistance to, or otherwise associate with, terrorists and terrorist organizations designated under the Order, as well as their subsidiaries, front organizations, agents, and associates.

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Legal Consequences

1.  With limited exceptions set forth in the Order, or as authorized by OFAC [Office of Foreign Assets Control], all property and interests in property of designated individuals or entities that are in the United States or that come within the United States, or that come within the possession or control of U.S. persons are blocked.

2.  With limited exceptions set forth in the Order, or as authorized by OFAC, any transaction or dealing by U.S. persons or within the United States in property or interests in property blocked pursuant to the Order is prohibited, including but not limited to the making or receiving of any contribution of funds, goods, or services to or for the benefit of individuals or entities designated under the Order.

3.  Any transaction by any U.S. person or within the United States that evades or avoids, or has the purpose of evading or avoiding, or attempts to violate, any of the prohibitions in the Order is prohibited.  Any conspiracy formed to violate any of the prohibitions is also prohibited.

4.  Civil and criminal penalties may be assessed for violations.

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Current List of Terrorists and Groups Identified Under E.O. 13224

For a current list, updated regularly, or terrorists and groups identified under E.O. 13224, see the 13224 List.

The Department of the Treasury, Anti-Terrorist Financing Guidelines:  Voluntary Best Practices for U.S. Charities (November 2002) also suggests that nonprofits and grantmakers check the following lists:

• Specially Designated Nationals and Blocked Persons List maintained by the Treasury Department’s Office of Foreign Assets Control (SDN List).
• Terrorist Exclusion List (TEL) maintained by the Department of Justice.
• The List of Individuals and Entities Belonging to or Associated with the Taliban and Al-Qaida Organization (1267 List)*
• EU List of Persons, Groups and Entities Involved in Terrorist Act (EU List)*

* Not referenced in the November 2005 Revised Guidelines