The filing deadline for the 2006 D.C. mayoral contest is two years away, and the smart money is already saying incumbent Anthony Williams probably won't run again. Of course, Williams won't confirm that, and for good reason. A lame-duck mayor such a long distance from Election Day would be eaten alive by the D.C. Council. But it's no secret that the mayor's wife, Diane, would just as soon see him leave office anytime within the past five minutes. That being the case, if calling it quits in 2006 is what Williams has in mind, it's not too soon for him to start thinking seriously about his legacy and how he wants to be remembered.

No doubt many D.C. residents already have their own thoughts. Where they stand on Williams and his gifts to the city depends on where they sit. And therein lies the problem when defining the mayor's legacy. Despite his six years in office, Tony Williams has never become the unifying force or the solid achiever he set out to be.

For some residents, especially those living in the more affluent or revitalized sections of the city, Williams is all they could want in a mayor: a brainy, apolitical, non-threatening public servant and a rather trusting soul to boot. For them, life is much improved under Williams, especially when compared with prior administrations. They will give him high marks.

For residents in decaying neighborhoods or in communities bypassed by the wave of development engulfing downtown and its fringes, Williams seems nothing more than the captive of powerful special interests out to convert the District into a booming shopping, dining and housing mecca for high-end users. The city's skyline, they say, is a case in point.

Construction cranes span the downtown horizon. Condominiums, office buildings, art galleries and trendy restaurants rise from the ground. The new faces of the District are well-heeled childless couples who aren't likely to burden either the schools or the criminal courts with their brand of problems. Making reservations is probably their most challenging event of the day. To them, the mayor's greatest gift is that he's not Marion Barry.

With Williams's arrival, out went demagogic racial rhetoric and a municipal reputation so poor that travelers were ashamed to say they were from the District. Williams and his team of planners and economic development gurus opened up the city for sale and converted the once-rejected District of Columbia into a gold rush for developers and a magnet for wannabe gentry. Years from now, future generations of gentrifiers may look back on the Williams era and mark it as the time in D.C. history when it all started to get good.

If that is how the mayor intends his years in office to be seen, he is on the right track. His legacy as the mayor who presided over the displacement of the city's poor and the arrival of the more affluent is safe for the ages.

He will be remembered, however, for even more than that if he doesn't change course.

If he is counting on the city's restored financial health to reflect well on his record, he is mistaken. A variety of actors, including the city's chief financial officer, the D.C. Council and Congress, can claim credit for the city's surpluses and the bond rating upgrades by Wall Street. And Williams also cannot claim responsibility for the District's red-hot real estate market. For that, thank the gift of a growing economy and the increased attractiveness of city living.

Tony Williams's legacy will be affected by the beleaguered public school system, dysfunctional youth and health agencies and the rootless children and families he leaves behind. Future District taxpayers -- and his successor -- to whom these problems will be bequeathed may not remember him so fondly.

He still has time to earn a lofty place in D.C. history. But he can't do it solely through bricks and mortar. When the name Tony Williams comes up among future generations, he should be known as the mayor who improved the quality of D.C. public education, who made the District government a shining example of efficiency, courtesy and effective public service. He should want to go down in history as the kind of leader who, through sustained demonstration of concern for the least among us and the high standards he set for himself, his administration and the community, inspired a generation of young people to turn their lives around.

Those -- not baseball stadiums, or a jazzed-up downtown and waterfront -- will be achievements worth remembering.

kingc@washpost.com