1979: The Metropolitan Museum of Art in New York City experiences its first theft in the museum's 110-year-old history on February 9 when an ancient Greek marble head valued at a quarter of a million dollars is stolen.

1988: Exactly nine years later, on February 9. two valuable Fra Angelico paintings are among the works stolen from a gallery in New York's wealthy Upper East Side, in the city's largest single art theft to date. Eighteen paintings and ten drawings valued at a total of $6 million are taken from the Colnaghi Ltd. gallery.

1990: The night of March 18, thieves enter Boston's Isabella Stewart Gardner Museum and make off with $300 million worth of art, including three paintings by Rembrandt, five by Edgar Degas, Edouard Manet, and the most valuable, The Concert, by Jan Vermeer. None of the paintings has been returned.

1997: In December, the Department of Justice and the FBI...