She wasn't just Mrs. John Lennon. One of the most challenging artists to emerge from the ferment of the 1960's avant-garde, Yoko Ono transformed music, film, performance, and language through her imagination. Working often with the simplest of objects - a chair, a chessboard, an apple, a cloth - she created complex and provocative events and visions with a distinctively Asian sensibility. Now it's time to step back and evaluate her work.

Walker Art Center, Minneapolis, March 10 - June 17(612-375-7622;
Contemporary Arts Museum, Houston, July 13 - September 16(713-284-8250;
Massachusetts institute of technology List Visual ArtsCenter, Cambridge, Massachusetts, October 18, 2001 - January6, 2002 (617-253-4400;
Art Gallery of Ontario, Toronto, February 22 - May 20, 2002(416-979-6648;
San Francisco Museum of Modern Art, June 22 - September 8,2002 (415-357-4000;

Grandma Moses in the 21st Century
Though Anna Mary Robertson Moses died in the 20th century and her works evoke earlier, simpler times, the paintings of this beloved self-taught artist have traveled well. The scenes of country work and play, of barns and sleigh rides and family festivals, are as fresh and honest as a sip of spring water. The more than 80 paintings on display include her last work, Rainbow, completed in 1961.

The National Museum of Women in the Arts, Washington, D.C.,March 15 - June 10 (202-783-5000;
San Diego Museum of Art, June 30 - August 26 (619-232-7931;
Orlando Museum of Art, September 15 - November 11(407-896-4231;
Gilcrease Museum of American History and Art, Tulsa,Oklahoma, February 23 - April 20, 2002 (918-596-2700;
Columbus Museum of Art, Ohio, May 11 - July 28, 2002(614-221-4848;
Portland Art Museum, Oregon, August 17 - December 1, 2002(503-226-2811;

William Blake
Organized by London's Tate Britain gallery and The Metropolitan Museum of Art, this is the first major American exhibit in several decades of works by the great Romantic poet, artist, and visionary. And high time! Skeptical yet God-obsessed, Blake foresaw the horrors of modern industrialization and authoritarianism, and his engravings, watercolors, and illuminated book illustrations presented an alternative, a world filled with innocence and light. The tiger burns bright in these more than 175 works.

The Metropolitan Museum of Art, New York City, March 29 -June 24 (212-535-7710;