It was a lesson that Sylvia Mathews learned earlier than most of her colleagues in the political world: When Bob Rubin phones, it's a good idea to take the call.

Seven years ago, when Mathews was working in Little Rock for Bill Clinton's presidential campaign, Rubin was an accomplished figure on Wall Street but not yet the central figure he would later become on the Clinton team. Rubin recalled that he would sometimes call the campaign to offer advice or seek talking points but had trouble getting the most senior aides on the phone. But he found he could always get results talking with Mathews, then in her twenties.

The man who later became treasury secretary said he found the woman at the end of the line had "good political sense, was extremely well-organized, bright as hell, very well-motivated."

Those 1992 phone calls turned out to be the start of a professional relationship that gave Mathews a place in the center of economic policymaking for the past seven years and vaulted her to a succession of senior, though largely unheralded, posts in the Clinton administration. At 34, the West Virginia native and former Rhodes scholar is now deputy director of the Office of Management and Budget.

She took that job last year after serving at the start of Clinton's second term as deputy White House chief of staff. She spent the first term by Rubin's side, as his chief of staff when he headed the National Economic Council and when he became treasury secretary. (Rubin left the administration this summer.)

As the senior subordinate to OMB Director Jacob "Jack" Lew, Mathews will be in the thick of the impending showdown between the administration and congressional Republicans over tax cuts and spending.

Mathews is one of the few senior Clinton officials to have served in the administration on an uninterrupted basis since the beginning, and she said she plans to stay until the end. While a president's influence often wanes toward the end of an administration, Mathews said she has no concerns that her responsibilities will become any less interesting, or her days less busy. "No matter what happens, we have to pass budgets," she said.

Mathews, who prides herself on her Greek-American roots, grew up in Hinton, W.Va., a town of about 3,000 people on the banks of the New River. Her older sister, Stephanie Mathews O'Keefe, said their "very well-organized, very, very focused" mother nurtured an interest in public policy and politics.

Few who have worked with Sylvia Mathews could doubt that those traits rubbed off. It was her strength in organization that attracted such figures as Rubin and former chief of staff Erskine B. Bowles to her. "She's very good at keeping an enormous amount of activity in motion," Rubin said.

While Mathews is generally well-liked in the White House, not everyone is as admiring of her professional style. Some current and former White House aides said she could become mired in bureaucratic process and detail. Some chafed at her affinity for meetings, protocol and management jargon learned in a stint with the McKinsey & Co. consulting firm.

At the White House, Mathews supervised the planning for two State of the Union addresses that were well-received, as well as Clinton's successful 1998 trip to Africa. Another major project that Mathews supervised, Clinton's year-long national dialogue on race relations, including the appointment of a commission to study the issue, had a more checkered record. Some participants complained that the effort bogged down in organizational and turf battles and had little substantive impact.

Mathews said the complexity of racial issues inevitably led to disagreement that kept the commission from doing more but said the project produced some solid achievements, such as a report on "best practices" detailing how some companies and communities have managed racial diversity to good effect. And she said her management style reflects lessons she has learned about getting results, both at the White House and the budget agency.

"There are many things that are process-related," she said. "A lot of the job is making things run, and a lot of time making things run is details."

Some colleagues and friends regard the OMB job as a better fit for her than deputy chief of staff. At the White House, she had more day-to-day contact with Clinton but faced a barrage of micro-decisions, including such minutiae as whether a local dignitary would ride in the president's limo during an out-of-town trip. The budget job involves far more time with policy substance.

National economic adviser Gene Sperling said that because Mathews "has already done so much at a young age on the management side, for her to spend so much time now on the policy side is a breath of fresh air."

Mathews, colleagues say, is a liberal who favors spending on social programs for the disadvantaged, but she and those who work with her say that much of her day-to-day budget work is not particularly ideological or partisan in nature. "Her role is less of an advocate and more of a problem-solver," said Sperling. "She's the person who keeps track of and has to resolve the often thorny and complex issues in the appropriations process."

Mathews, for instance, has helped put together the administration's supplemental appropriations bills. In recent days, she has been working with agencies and juggling accounts to find earthquake relief aid for Turkey.

On the wall of her spacious Old Executive Office Building office is a map of West Virginia. Some friends think going back there to run for governor or another office would be a logical step for Mathews. She says she plans to go to the private sector when the administration ends but does not preclude seeking office "if I had a vision about what I wanted to accomplish."

A family friend, Sen. John D. "Jay" Rockefeller IV (D-W.Va.), hopes she does it. Rockefeller, who said he considers Mathews a "Greek goddess," said he believes her "small-town origins" stoked ambition for her to compete and excel outside the state, on campuses and in Washington, and that these traits might eventually bring her home to her native state. "She'd have to go back and do due diligence," he said. "I'd love to see it happen."

Players

Sylvia Mathews

Title: Deputy Director, Office of Management and Budget

Age: 34

Education: Harvard University with a degree in government; Oxford University (Rhodes Scholar) studying philosophy.

Family: Single

Previous job: Campaign aide to 1988 Democratic presidential nominee Michael S. Dukakis; associate, McKinsey & Co.; chief of staff, White House National Economic Council; chief of staff, Department of Treasury.

Interests: Biking, hiking and voluteering with nonprofit groups.

On what she does as the administration's No. 2 budget official: "I see my job to be even-handed in making sure all the president's priorities get addressed, and that everyone has a seat at the table, rather than being a policy advocate."

CAPTION: Sylvia Mathews, deputy director of OMB, began working for Clinton in 1992.