REGIONAL PLANNERS tell the story of a senior engineer involved in the plan to build express toll lanes on the Capital Beltway in Northern Virginia and his slightly misplaced exuberance at what he imagined would be a brighter transportation tomorrow. In a public forum, the engineer enthused that drivers from Maryland crossing the American Legion Bridge would see the road open up once they reached the widened Virginia side: what a vista! What he didn't mention was the return trip into Maryland, where traffic would very likely slow as the Beltway narrowed.

The anecdote encapsulates the curious disconnect between Virginia's left hand and Maryland's right, which too often seem clueless about one another's doings. Until a few years ago, the two states' governors sat down together and communicated with all the enthusiasm that separated couples bring to divorce court: meetings were few, far between and finished with all due haste.

The states' current leaders, Govs. Mark R. Warner (D) of Virginia and Robert. L. Ehrlich Jr. (R) of Maryland, have changed that, to the region's benefit. Last week, along with D.C. Mayor Anthony A. Williams (D), they met for their fifth "summit" in 21/2 years. The session was especially fruitful, as the governors took a tentative first step toward adding 28 miles of express toll lanes on both sides of the Potomac River. The idea of express toll lanes all the way around the Beltway has been kicked around by transportation officials for some time. But big projects need big-thinking leaders. And by agreeing to launch and pay for a pair of studies, Mr. Warner and Mr. Ehrlich sensibly, if briefly, shed their partisan stripes and sketched a coordinated long-term strategy to address the deluge of suburban traffic. At this rate it may even be possible to conceive of Beltway traffic moving on both sides of the river.

While they were at it, the mayor and two governors agreed to seek a joint meeting with Homeland Security Secretary Michael Chertoff; discussed ways to revive the Chesapeake Bay and its oyster harvest; and touched on nanotechnology and tourism. In other words, they talked business. That may seem all in a day's ho-hum work, but around here it's a refreshing change for the better.