After a shaky four-year trial, the concept of promoting the Baltimore-Washington region as a single market for economic development may be gaining the viability proponents of the idea have sought.

With its notion of regionalism blessed by no less than an official of The Fantus Co.--one of the world's leading consulting firms in business site location--the Washington-Baltimore Regional Association (WBRA) has every reason to feel vindicated.

Although the organization has established a stronger identity over the past year, parochial interests and competitive priorities of local jurisdictions remain as hurdles to greater involvement by business and government leaders.

WBRA is an alliance of business leaders from throughout the region working to promote economic development within the Baltimore-Washington Common Market.

At their annual meeting this week, members of the organization were assured that there clearly is a necessity for a common market.

In fact, the Baltimore-Washington common market concept had to be developed for several reasons, said L. Clinton Hoch, executive vice president of The Fantus Co.

Fantus has been consultant to major investors in the region over several years, beginning with Reston founder Robert Simon. The Rouse Co., AT&T, Westinghouse Corp., and Mobil Corp. have also consulted Fantus about investment in the region.

As far as a common market is concerned, two reasons provide perhaps the most objective and persuasive arguments yet for the concept, and Hoch's analysis should prove valuable in future efforts to sell the two areas as a single economic entity.

To begin with, says Hoch, the common market concept had to be developed to demonstrate what he calls its "togetherness." The WBRA, he implied, is on target in emphasizing the unique strengths of the combined metropolitan areas.

It's also implicit in Hoch's assessment that in focusing on those strengths, the weaknesses of the individual metropolitan areas become less noticeable.

Metropolitan Washington, for example, is one of the nation's least industrialized urban centers, but Baltimore ranks among the largest manufacturing complexes.

Hoch's thesis reflects a great deal of what advocates of the common market concept have been saying, albeit in somewhat fragmented ways most times. Other examples which make the point:

Only two of the Fortune 500 leading U.S. industrial corporations maintain their headquarters in metropolitan Washington but that number increases to seven when the total market includes the Baltimore standard metropolitan statistical area (SMSA).

Individually, Washington and Baltimore lack some elements that are important to a transportation infrastructure, but the region contains a full spectrum of air, land and sea services.

Baltimore has a fair amount of cultural attractions but when those are considered in conjunction with what Washington offers, the region is in a stronger position to challenge other centers for supremacy in the arts.

Hoch further suggests that another reason for developing the Baltimore-Washington common market concept is marketability. The region as a whole, he observed, demonstrates statistical strengths, although its components may have statistical weaknesses.

Statistical strength of the region is an important factor for several reasons in a changing national economy, Hoch asserted.

A trend toward increased decentralization of service offices has become apparent in every part of the financial industry, he noted. But the shift is accompanied by a parallel movement toward consolidation of regional offices in key centers, he said.

Thus, Hoch observed, "stand-alone facilities may not be viable in either Baltimore or Washington, but an office serving the whole region may be entirely feasible."

Hoch cited another trend toward smaller, specialized manufacturing facilities, in response to new production equipment and automation. "Demonstrated regional demand can be expected to dominate the decisions to establish these new, smaller plants keyed to concentrations of demand," he said. "The implications for warehouse distribution are obvious."

The implications of a recent Fantus market survey may be even more significant in terms of future WBRA promotion efforts. As an independent study, Fantus' findings lend a credibility to the Baltimore-Washington common market concept that is far more persuasive than what might otherwise be viewed as boosterism by local interests.

The findings are based on a study prepared for a major U.S. real estate securities firm that requested a list of the 25 most likely places for investment value growth over the next five to 10 years. Based on Fantus' analysis of 154 SMSAs, Washington and Baltimore ranked fifth and 25th, respectively.

But when the regional concept was applied in a further series of statistical analyses, the Baltimore-Washington ranked No. 2, behind Dallas-Fort Worth.