A few days after winning the presidency of Fairfax County's smaller teachers union, Mark L. Glaser made an unlikely phone call -- to the head of the rival union.

"The way it's been for the last twenty-some-odd years isn't going to work," he said. "We need a unified approach."

In a month at the helm of the Fairfax County Federation of Teachers, Glaser said, he has been trying to moderate and refocus the 3,100-member group, which frequently sparred with former superintendent Daniel A. Domenech and issued scathing press releases against him and the Washington area's largest school district. In turn, school officials and politicians often ridiculed the federation and gave its views little consideration when formulating district policies or the annual budget.

Now, Glaser wants the group to be taken more seriously, and much of his strategy depends on cooperation with the county's much larger teachers union, the 6,500-member Fairfax Education Association.

For as long as anyone can remember, the groups have not gotten along very well. In Fairfax, the federation tends to back Republican candidates, while the association generally endorses Democrats. While the federation has advocated phonics-based reading instruction, the association has stressed combining a whole-language approach with phonics. The federation has favored math textbooks that emphasize drill; the association has supported books filled with word problems.

"There has been very little relationship," said Barbara Allen, president of the Fairfax Education Association. "The philosophical views of the FEA leadership and the federation have been diametrically opposed. It's never been a good relationship, and there's very little commonality."

To some extent, the tensions in Fairfax reflect a rivalry between the national umbrella groups, the American Federation of Teachers and the National Education Association, which will hold its national conference in Washington this week and next.

The larger NEA, founded before the Civil War as a professional group, has a membership rooted in suburban and small-town America. The AFT, formed in 1916, modeled itself after Detroit's militant auto workers and has a stronghold in more urban areas.

Although the national groups have rejected proposals to merge formally, labor analysts say tactics such as Glaser's are increasingly common in jurisdictions across the country.

"It makes no sense for sister unions to be at each other's throats," said Adam Urbanski, president of the AFT-affiliated Rochester Teachers Association and the founding director of the Teacher Union Reform Network, which includes various educators unions. "We have a lot more in common than we have to fight about. The reaching out by the AFT and NEA affiliates in Fairfax is both a very good thing and a very necessary thing."

But the Fairfax Education Association, which generally enjoyed harmonious relations with Domenech, remains skeptical. "They have nothing to lose but to offer to be more collegial and have a more positive working relationship," said Allen, whose term expires this week. "At this point, they need to build upon their own credibility within their own union before there's a lot that we would see doing together."

She wondered whether the federation in Fairfax would change course on its advocacy of phonics-based reading programs and endorsements of more conservative candidates.

But Glaser said such issues are secondary to his main mission of raising teachers' pay by 30 percent over the next three years. Average pay for Fairfax teachers is $55,265 annually, and increased 7.1 percent in next year's budget.

"Our teachers are shopping in thrift stores. They have to live with their parents. They are using credit cards to make ends meet," Glaser said. "We are going to stick with the issues of teacher salaries. I'm not going to get involved in curriculum issues."

Despite his attempts, Glaser said the militant focus of the Fairfax local will remain. "This is a contrarian, vociferous group," he said. "It was always a group that wasn't afraid of a fight. That's the only way I'd go."

In his last year in Fairfax, before leaving in March for the textbook publishing industry, Domenech made no secret of his distaste for the federation, its practices and past presidents Judy Johnson and Rick Nelson. In March 2003, after Domenech and Johnson exchanged a series of nasty letters, the superintendent agreed to meet with the union membership. Some educators, citing low pay and a lack of respect, heckled Domenech, who grew visibly angry, gulped down water and threatened to leave.

Although he stayed until the end, the meeting marked a turning point. For the rest of his tenure, Domenech ridiculed the federation's press releases and accused leaders of employing "fuzzy math" on such matters as funding and staffing.

"He had a point," said Glaser, who said he remained silent and embarrassed at that meeting. "The FCFT looked awful. . . . The adversarial relationship with management caused us not to be heard."

Glaser said Johnson and Nelson no longer speak for the union and are no longer on the staff. Johnson, who lost her bid for reelection to Glaser, said she would not comment, and Nelson did not return phone calls for comment.

Glaser said he plans to reach out to School Board members, supervisors, assistant superintendents, principals and teachers. Already, school officials said they see a difference.

"I have talked with Mark on several occasions, and I am looking forward to a more productive, collaborative association with the FCFT," said Kevin North, the district's assistant superintendent for human resources. "My past meetings with Judy and Rick were on very specific, tactical issues rather than looking at the overall direction of their organization."

In Virginia, where teachers can choose not to belong to any employee group, unions often must prove their relevance to members. Glaser conceded that a dwindling membership base also sparked the union's efforts to change.

"The membership wants us to represent them for better conditions, but they don't want us to be as confrontational as in the past," Glaser said.