Here's an essential exhibit (if only virtual) for anyone interested in the 20th-century Russian avant-garde.

For this Triennial, the curators stepped aside and let artists make the call. The result is fascinating.

On Sunday a plaque went up on the apartment house that was the Last Address of a great avant-garde painter.

When we witnessed the fall of the Soviet Union 20 years ago, we also witnessed the fall of its monuments. The general impression was that we were...