The Arlington County Board's Republican majority is expected to select this Monday a partnership headed by the Charles E. Smith Co. as developer for its massive Courthouse Metro stop project, starting a process that county officials hope will set the pace for development on the county's aging Wilson Boulevard corridor.

In so doing, Arlington will lead local jurisdictions that have dreams of cashing in on government-owned land values vastly increased by the arrival of the Metro subway system.

"They're in the forefront," said M. Richard Miller, Metro's development manager. "Arlington has recognized that the adjacency of Metro stops is something that can help shape the county's future as well as provide for revenues."

County Board Chairman Stephen H. Detwiler and board member Dorothy T. Grotos, both Republicans, said yesterday that they will support the selection of a partnership between Smith, the firm which developed Crystal City, and the Artery Organization, a Chevy Chase-based town house developer.

Walter Frankland, the third Republican on the five-member board, has said publicly that he supports a county selection panel's endorsement of the Smith-Artery plan.

"I'm committed to following the recommendation of the selection panel," said Grotos. "I don't see how board members can expect to get the insight in a couple of hours when this panel spent months on it."

That panel included Frankland, private citizens and Democratic board member John G. Milliken, who yesterday declined to say which developer he planned to back. Democratic-backed independent Ellen M. Bozman could not be reached for comment. With the Nov. 2 defeat of Detwiler by Democrat Mary Margaret Whipple, the Republicans will lose their board majority next year.

Smith-Artery's Courthouse Plaza proposal for a $120 million to $150 million project that would include county offices as well as retail and residential space is one of three to be considered by the board Monday night.

The county had asked bidders to submit plans for projects that would include 30,000 feet of county office space and would serve as an anchor for development along Wilson Boulevard.

After the County Board has selected a developer, it will commence final negotiations over the development plan and the financial arrangements of the joint venture. Completion of the first phase of the project is not expected for two to three years, county officials said.

The chosen developer wins the right to lease or buy 6.4 acres of prime county land across the street from the Courthouse stop, where the project will be built. The site, bounded by North 15th, North 14th and North Adams streets, is currently being used as a gravel-topped county parking lot.

"This project is important, not just because of its contribution to the county's economic base, but because it will be a catalyst, a spark for development in the courthouse area and the whole Metro corridor," said Thomas C. Parker, the county's director of economic development.

Smith-Artery's proposal calls for three public squares connected by meandering sidewalks. It would include two 12-story office buildings, a 30,000-square-foot addition to the County Courthouse, a 23-story hotel and 40,550 feet of retail space.