Stockbridge, Mass.

ALTHOUGH Norman Rockwell’s ability to capture small-town bonhomie made him the leading illustrator of his time, these days his vision is often derided asanachronistic and hokey. One might expect the museum that manages his legacy to be similarly stuck in time. But Rockwell himself was more complex and worldly than is often acknowledged today, and so is the Norman Rockwell Museum here — what some might call a hip and savvy institution masquerading in square clothing.

Capitalizing on an abiding public interest and good will toward the Rockwell name, it has managed to mount popular exhibitions devoted not just to him but also to other illustrators, cartoonists and political satirists, complete with serious scholarly catalogs. And on Tuesday, Rockwell’s birthday, the museum announced that it would extend its influence through the creation of the Rockwell Center, which will transform the museum into a nexus for the study of American illustration art, a woefully neglected field.

For a museum founded primarily as a showcase for the work of a single artist, expanding the mission in this way may seem an unusual departure. Yet it is a common strategy for single-artist institutions, like the Georgia O’Keeffe Museum in Santa Fe, N.M., and the Andy Warhol Museum in Pittsburgh. Broadening the focus is regarded as a way to show the work in context and keep the reputation renewed, as well as widening avenues for funding.