PEOPLE IN THE Washington area as elsewhere are always in the market for ways to encourage growth; the incentive, obviously, is in the increased tax revenues that come from new development. The problem is equally obvious: how to prevent such new development from overwhelming existing neighborhoods and public facilities. The blunt-instrument approach - for instance, imposing a moratorium on sewer construction - has been only partially satisfactory, at best. What is needed is a more careful and comprehensive method of tailoring development to the available facilities.

That there is such a method is demonstrated by a recent Maryland Court of Appeals decision upholding a Montgomery County plan that sharply limits future growth in the flourishing commercial and residential enclave of Friendship Heights. By affirming the county's right to carry out the plan, the court in effect endorsed the idea that officials in those Maryland counties with home-rule powers are in the best position to judge precisely how to accommodate an area's development needs to such environmental considerations as the capacity of the area's streets and sewers. That's what the Friendship Heights plan does and does well, in our view.

Clearly, this commercially valuable area just across the District line had to do something to control its development. Not only is it a major gateway to Washington for commuter traffic (and soon to be the site of a Metro rail station); it's also a fashionable shopping district whose department stores and specialty shops draw customers - most of them travelling by automobile - from the entire metropolitan area. The inevitable result, especially during the rush hours, is traffic jams, which county officials indentified as the most important reason to restrict future development there. An additional 16 million square feet of commercial space could have been developed under the county's previous zoning rules, but the only at the expense of truly mind-boggling traffic problems. The lengthy public hearings, allow the development of only a tenth of that space. Still, officials estimate that even the limited development will increase by 11,000 the number of vehicles on the streets during the peak rush hours.

The Court of Appeals was concerned with the process, not the merits, of this particular dicision. Understandably, some have expressed concern that it could lead to a spate of arbitrary actions by officials, either for or against development. We don't think that will happen. The Court's emphasis on the fairness of the process Montgomery County officials used is and indication it won't in the future look favorably upon decisions reached in a capricious or discriminatory way. The more probable result of this ruling, if other jurisdictions emulate the care and impartiality shown in Montgomery County, will be a more rational, responsible planning process.