The 200th Anniversary of the Act Prohibiting Importation of Slaves was January 1, 2008. A United States federal law in accordance with the Constitution of the United States that no new slaves were permitted to be imported to the United States. This act effectively ended the legal transatlantic slave trade. The entire text of this act is available here at TeachingAmericanHistory.org.
Many organizations around the world are celebrating this anniversary with informative programs and exhibits. Below are links to a few key resources
United States National Slavery Museum
International Slavery Museum in Liverpool
Atlantic Slave Trade Institute