When Lonnie G. Bunch III outlines plans for the National Museum of African American History and Culture, the historian can barely sit still. This is a buoyant man on the move, overseeing the design for what could be the last major building on the National Mall; urging citizens to bring their family mementos out of the attic; deciding which stories out of more than 400 years of American history should be told; and preaching the necessity of this enterprise.

"This is a museum about African-American life, and African-American life is a lens on what it means to be an American. And we talk about how this is everyone's story. And anyone I can get in front of ends up understanding our purpose," says Bunch, 58, a native of New Jersey, and a specialist in 19th-century American history. His professional career has been steeped in museum building and expansion, including the California African American Museum in Los Angeles and the Chicago Historical Society. Bunch was the supervising curator at the National Museum of American History from 1989 to 1992 and returned to the Smithsonian in 2005 to build the new museum. Now he's the founding director of a high-profile project in Washington that everyone is watching closely.

In his office in D.C., Bunch describes the status of the critical elements needed for the museum to open in late 2015. He walks over to a refined museum model, designed by Freelon Adjaye Bond and SmithGroup. On a 5-acre site, directly in the shadow of the Washington Monument, the building will have three coronas of shining metals, and the exterior walls will reflect some of the signature styles of New Orleans and Charleston, S.C., ironworkers. The proposed design has been condensed from an original model. "Now it sits on the earth as a pristine jewel box," says Bunch, reviewing all the details that will make it a destination.

The fundraising for the $500 million project, authorized by Congress in 2003 as part of the Smithsonian Institution complex, has progressed beyond projections, despite the recession. That status prompts a huge smile from the bearded and bespectacled Bunch. "My thought was that the fundraising would pick up after we had drawings and a model. But we had $70 million before the drawings," says Bunch. Congress has pledged half of the goal, with $125 million in the 2012 budget and $85 million penciled in for the next year.

The challenge with building a museum from scratch is developing the content and collecting the artifacts. All along, Bunch has said he wanted several large objects, not only to be showstoppers but also to reflect the work, achievements, joys and tragedies of black life. The museum was given an original railroad car, divided into colored and white sections. Bunch also has his eye on a slave cabin.