In the continuing battle between chain stores and watchdog groups over the fate of Harvard Square, the Harvard Square Defense Fund has sued to prevent a Starbucks coffee shop from renting space on Church Street.

Cambridge's Board of Zoning Appeals (BZA) ruled unanimously that a Starbucks could be opened on Church Street. But the defense fund has filed an appeal in court.

According to G. Pebble Gifford, president of the defense fund, the city's fast food ordinance, which regulates such cases, requires among other things that there be a need for a new establishment.

Gifford said that with Starbucks stores in the Garage, on Mass. Ave. and on Broadway, there is no need for another franchise.

"We are ringed in by Starbucks and one is enough," Gifford said.

However, Alexander M. "Sandy" Cahaly, who owns the property on Church Street as well as Cahaly's on Brattle Street, said that need is not a problem.

"The BZA did not get into the need aspect of it because this becomes a constitutional thing," Cahaly said. "What dictates the need for Harvard Square or any area is the consumer on the sidewalk."

"We must not forget that this country has a free enterprise system," he said.

Gifford, however, said the high concentration of Starbucks in the area is due to a marketing ploy that ignores the needs of the community.

"Apparently, their theory of marketing is saturation. This is the antithesis of the defense fund, which is we're going to work with the small stores and avoid duplication," said Gifford.

"The idea of three or four Starbucks may be fine from their marketing point of view," she said, "but it doesn't do a darn thing for Harvard Square."

Gifford also pointed out that there are at least two dozen seated shops serving coffee in Harvard Square south and west of Mass. Ave.

Cahaly, however, said he thought another Starbucks would be a good addition to the Square.

"I have had a couple of million cups of coffee in Harvard Square and I think a person would rate Starbucks as among the best," he said.

Cahaly also noted the property was previously rented by Steve's Ice Cream, which had a market similar to that of Starbucks.

"What we had in that building was Steve's Ice Cream, which sold coffee and sandwiches and pastry, and that's what Starbucks sells," Cahaly said.

He said he did not think the proximity of the two Harvard Square stores would be a problem.

"Where the Garage is and where Church Street is are two distinctly different areas of the Square," Cahaly said. "I would definitely think that Starbucks would be successful."

The customers at the Starbucks in the Garage had mixed responses to the idea of another store on Church Street.

"No, definitely not," said Craig Welsh, a Somerville resident, when asked if there was a need for another Starbucks. "I'm against Starbucks. They're taking over the world."

Divinity School student Rebecca J. Lotzer, however, disagreed.

"I think Harvard Square can always use more cafes, especially ones that are friendly to students by having more tables and letting you stay for a couple of hours," she said. "Starbucks is pretty successful at that.