Dozens of studies have documented population and economic growth in metropolitan Washington in recent years, but they have tended to tell politicians and boosters what they want to hear: The Washington area will continue to attract bright people with high incomes, and the economy will continue to expand.

Studies of demographic trends, housing, poverty and job growth, for example, have tended to reinforce the assumptions and biases people have about the region's economy. Few, if any, have examined these issues in the context of social distress vs. prosperity.

But, alas, a new report released this week by the Brookings Institution, on the state of growth in the Washington area, fills that void.

Commissioned by Brookings's Center on Urban and Metropolitan Policy, the report is based primarily on a more extensive report, Washington Metropolitics, by metropolitan researcher Myron Orfield.

The Brookings report is not your garden-variety study of the local economy. Instead, it is an unusually candid assessment of growth in the region and how it's being shaped by race, social ills and other factors that are rarely discussed openly. It's must reading for every public official and business leader in the region.

Doubtless most would agree with the report's general conclusion that the region is wealthy and that it has many economic, historic and natural assets that will continue to attract people and businesses. Those assets will keep the region's economy humming, the report adds.

But it's what the report has to say about potential challenges to this growth and prosperity that sets it apart from most studies on the subject.

This is a region divided by race, class, ethnicity, jobs, income and opportunity, the report concludes, based on extensive research and analysis of socioeconomic and growth trends. Hence the title, "A Region Divided: The State of Growth in Greater Washington, D.C."

That the region is divided along racial, social and economic lines is not a startling conclusion by any means. It's just that no one has dared to acknowledge it publicly until now.

They tend instead to compare growth in the District with that in the suburbs, marveling at the strength of the economy outside the city. Similarly, comparisons between Northern Virginia and suburban Maryland frequently shape discussions about growth in the region.

But as the Brookings report makes clear, the story of growth in the region's economy isn't about city vs. suburb. And neither is it about Maryland vs. Virginia. It's about a region that is "out-of-balance, struggling with the consequences of very little growth on one side and an extraordinary amount on the other."

More to the point, researchers explain in the report, the eastern portion of the region, primarily the District and Prince George's County, bears the burden of poverty, while the western part enjoys the fruits of prosperity.

Even so, researchers maintain, the social, racial and opportunity line dividing the region runs through many of its counties and the District, separating the affluent from the poor. Seventy percent of the area's black population nonetheless resides in the District and Prince George's County.

There are exceptions. Clearly, communities west of 16th Street in the District are among the more affluent in the region. High-income communities outside the Beltway in Prince George's County are also exceptions to the pattern of a divided region.

At the same time, school districts in the nation's capital and Prince George's and Arlington counties have the highest percentages of students eligible for school lunch subsidies.

Other studies have at least documented that much. But the Brookings researchers had the courage to conclude that this pattern demonstrates the region is "starkly divided by race" and that it is "racially segregated."

It might have been useful if the report had attempted to explain how the region became divided by race, income, jobs and opportunity.

What's more important, however, is that the Brookings study has exposed the folly of continuing this absurd pattern, which has serious implications for continued growth.

Rapid growth in some communities and limited growth in others are "inextricably linked," researchers concluded in the report. Poor neighborhoods with high costs, low services and failing schools push out families with resources. This flight not only weakens struggling communities but also puts added pressure on more prosperous rapid-growing areas, they noted.

Whatever its shortcomings, the Brookings study is a compelling challenge to business leaders and policymakers to move beyond the divisions identified in it and "embrace a future that is economically sound."

Maintaining the status quo is certain to produce more sprawl, more congested roads, more pressure on local budgets and further increases in lost productivity in the workplace. (For more information on the report, see www.brookings.edu.)