Striking a balance between the redevelopment of commercial areas and the retention of "essential" businesses is often made more difficult than it should be by public sector officials. A fair number of officials are, in fact, reluctant to manage change in a way that will accommodate both developers of commercial projects and businesses threatened by new construction.

Indeed, public officials have often been too willing to relinquish their responsibility in determining the mix of business and residential, or of office and retail, in old commercial districts. An official at the Downtown Partnership, the public-private initiative established by Mayor Marion Barry in 1984 to manage revitalization of the old business district, recently suggested that the area's office boom and the displacement of small businesses are results of inevitable change. "We have a situation that's enviable," he noted. "I don't think we fear change. We want to manage change."

That's made easier when public officials fully understand all that development encompasses and the power of public intervention. The opening of Safeway Stores' Food Emporium on Wilson Boulevard last month might not have occurred if Arlington County officials hadn't understood either concept.

The Food Emporium, which actually is a replacement for a Safeway store that had been on the site, is on the basement level of an office building developed by The Kaempfer Co. The 31,000-square-foot store has been customized for a special market segment in Arlington: office workers and residents of nearby apartments, condominiums and town houses. The store is accessible to walk-in traffic or from a parking garage in the office building.

Safeway officials describe their new emporium as the "most phenomenal" specialty services food store around. Customers and competitors will be the final judges of that. It is, nevertheless, an ambitious concept that has strong potential for replication, not only because of the merchandise mix but also because of the way it has been integrated into a major office complex.

Although selling space is limited to only 21,000 square feet, the store features a full-service deli, salad bar, self-service soda fountain, pharmacy, floral department, fresh seafood section, fresh produce and a wide selection of beer and wines, in addition to conventional grocery items. To accommodate so many specialty features, Safeway officials carefully selected the mix of conventional grocery items to fit the needs of the store's primary customers. Instead of carrying three or four sizes of some products, for instance, the store carries only one or two to save shelf space.

The point here is not that Safeway has opened a new store or that this is one way of increasing the number of supermarkets in urban areas. The Safeway specialty store could have been a furniture store, a hardware store, a shoe store or any retail outlet that public officials consider an essential consumer service for people living in nearby residential communities.

In this case, however, Arlington County officials made it clear that broadening the retail food industry in the county was a priority. Shortly after the Grand Union Stores pulled out of the county in 1985, county officials not only developed an action plan but also brought industry representatives and developers together to make them aware of the priority.

When Kaempfer acquired the Wilson Boulevard site, "he knew the county's interest" in having a replacement Safeway store there, recalled Thomas C. Parker, chief of Arlington County's economic development office. "And, indeed, when the site plan came in, {Kaempfer} didn't have a deal with Safeway but the plan included space for a supermarket."

Arlington County's zoning laws, like those in other jurisdictions, stipulate the floor-area ratio, or the maximum amount of floor space that can be built on a given site. "In this case, the county zoning board made an exception and didn't include the grocery store {space} against the FAR," Park said.

In other words, Arlington County used a zoning incentive to achieve the developer's goals as well as its own in balancing commercial development interests against other interests.

Zoning incentives have been used before in the county, but this is the first time, according to Parker, that they were used to retain or attract an essential business service. Success in putting the Kaempfer deal together strongly indicates it won't be the last time that kind of zoning incentive will be used in Arlington County.

In the meantime, Safeway officials are calling the Food Emporium "a supermarket of the future" and one that can be profitable in the right location -- "surrounded by offices and walk-in traffic."

Again, it's not the supermarket per se that's important here. Of more importance is the fact that Arlington County clearly demonstrated what can accomplished when there is strong commitment to a public intervention policy.

The supermarket might well have been a cafeteria that was considered essential service for senior citizens living nearby.

What matters is that, in this case, public policy was used to strike a balance between private-sector interests and those of the public.

It is a model that can be replicated just as effectively in downtown Silver Spring or in downtown Washington.