The American Speech-Language-Hearing Association may be a savvy trade group on Capitol Hill, but it's getting a hard lesson in suburban politics from Montgomery County residents who are fighting the association's plan to develop the site of its North Bethesda headquarters into an office park.

The association filed a petition to rezone the property last year so it could develop up to 350,000 square feet of office space on the 11 acres surrounding its headquarters and lease it to other groups.

But after alternately wooing and battling nearby residents for nine months, the association has asked the Montgomery County Planning Board to postpone a hearing on the rezoning.

"We filed a plan with our rezoning request, but that has been revised pretty extensively. Basically it's out the window," said Alton Fryer, a vice president with Spaulding and Slye, a Boston-based firm that is managing the project.

Fryer said his firm is developing a "better approach" to deal with citizen concerns, but declined to elaborate.

The 20,000-member association, which represents practicioners who work with individuals whose speech, hearing or use of language is impaired, wants to develop the property to generate income for its various programs, said Executive Director Frederick Spahr.

Although the area is zoned residential, the association's headquarters at Rockville Pike and Strathmore Avenue is next to three other institutions: Georgetown Preparatory School, the Academy of the Holy Cross and Strathmore Hall, a county-owned arts center.

Because all are within shouting distance of the new Grosvenor Metro station, they are considered prime sites for development, said Joseph R. Davis, a county planning and zoning analyst.

"We get developers knocking on my door at least once a week," said Georgetown Prep's president, the Rev. Jerome Coll.

Coll said the 196-year-old school also is interested in developing some of its 90-acre campus, although it has no immediate plans to do so. "We have to consider the resources that are going to be necessary to take care of the school for the next 200 years," he said.

The association, without citizen opposition, built its 40,000-square-foot headquarters in the mid-70's under a special exception to county zoning laws that permits nonprofit, philanthropic organizations in residential areas.

But this time, the Town of Garrett Park, a small municipality with a post office and 350 homes -- all of which are on the National Register of Historic Places -- is leading the fight against further development.

The town council and the Garrett Park Citizens Assocation voted to oppose the association's plan last fall. Three citizen associations in the nearby Grosvenor Park condominium project are supporting the plan.

Garrett Park residents object to the extra traffic that they say will spill from the the development onto Strathmore Avenue, a residential street that doubles as the town's main thoroughfare, Mayor Laura C. Pratt said.

According to a Spaulding and Slye report, the association had proposed a 1,000-car parking lot for the office park that would have generated a 14 percent increase in rush-hour traffic on the two-lane avenue.

The town also opposes the rezoning, because it would set a precedent that ultimately could change the character of the area. "It essentially would create a commercial park . . . in an entirely residential area," Pratt said.

Technically, the group could develop the property under another special exception, but tenants would be limited to philanthropic groups, said zoning analyst Davis.

Meanwhile, the rezoning hearing has been rescheduled for April.

"We're trying to achieve the best low-density, low-rise development for the site that we can," said Fryer. "We think we'll have one by then."