Contributors to this guide include editorial interns Jason Breslow, Mayank Bubna, Kate Ghiloni, and Katie Volin; assistant editors Kimberly Forrest and Mary Clare Fleury; online editor Ann Limpert; and assistant photography editor Anne Sterrett.

In the past decade, more than $1.5 billion has been pledged to or spent on Washington museums. It's been a generation since the last golden age of museums. In the 1970s, the Mall welcomed three additions, each breaking new ground--the curvaceous Hirshhorn, the mammoth National Air and Space Museum, and I.M. Pei's abstract East Wing of the National Gallery of Art. Together they upset the Mall's marble-columned orthodoxy, the legacy of neoclassicists like John Russell Pope, who designed the National Archives and the original National Gallery.

Today's museum boom is sending similar shock waves through the Mall and beyond. The Corcoran Gallery of Art hopes to break ground next year on a $120-million wing--a Frank Gehry-designed building of undulating metal. The Newseum is scheduled to reopen in 2007 on Pennsylvania Avenue, introducing a new six-story glass structure--designed by the architecture firms that helped create Bill Clinton's presidential library--across the street from the marble creations of Pope and Pei.

The culture craze extends to the suburbs and beyond, with museums debuting or in the works at Quantico and in Lorton and Winchester. Chien Chung Pei, I.M. Pei's son, is designing a National Slavery Museum in Fredericksburg.

More than a few museum projects are seen as economic engines. Only about 40 percent of the 555,000-square-foot Newseum complex will be devoted to museum exhibitions and operations. The rest will house, among other things, office space, stores, and condominiums--features that DC hopes will fuel the resurgence of Penn Quarter, already home to the hot new International Spy Museum and the soon-to-be-reopened American Art Museum and National Portrait Gallery.

The Capital Children's Museum, which closed near Capitol Hill, will reopen in 2008 as the National Children's Museum in a $100-million facility at L'Enfant Plaza. It'll anchor an office/retail/residential development that planners hope will help spark renewal in Southwest DC.

For the museumgoer, we offer a guide to more than 150 area attractions. We highlight must-see treasures, hidden gems, and summer shows, plus suggest where to get good food and great gifts.