The D.C. Zoning Commission is probably not the worst such body in the United States, but it must come close.

As a city, we were intended to be uniquely monumental and commemorative to all Americans. The commission, though, has permited developers to go through this city like Grant through Richmond. Some members of the commission seem to have never met a development they didn't like -- for them, no mass is too massive, no density too dense, no height too high and nothing historic sufficiently so.

Look at one great avenue -- Pennsylvania -- for example. Here, despite the L'Enfant plan, the Kennedy plan, the Pennsylvania Avenue development plan and now the comprehensive plan -- buildings like the Marriott Hotel monstrosity at 14th and Pennsylvania sit astride our great national square, a stone's throw from the White House and just across the avenue from the majestic District Building.

Other examples of the work of this commission are on view all around us -- in the erosion of residential zones and in the demise of almost every town house, row house and low-rise structure of any kind, commercial or residential, south of Massachusetts Avenue.

But nothing epitomizes the failure of the commission to protect the integrity of the city than the proliferation of Planned Unit Developments. PUDs, which grant zoning variances for relatively large-scale development on small parcels of land, have proven to be especially intrusive in residential zones.

Many magnificent and historic blocks now are threatened with PUDs, including the Riggs bank project at Dupont Circle, the 1700 block of N Street NW, the 2200 block of N Street NW (where demolitions have already occurred) and the 1700 block of Rhode Island Avenue NW, where a towering redevelopment project threatens to overwhelm St. Matthew's Cathedral.

The so-called "amenities" developers are required to give to the community in exchange for PUDs are not always substantial, visible or on-site and are sometimes shifted elsewhere under the "linkage" program. How does that help the neighborhood that ends up with commercial development on its doorstep? PUDs should be declared a failure in zoning policy and abolished.

Even when the commission tries to throw a bone to the community by endorsing pockets of housing in downtown development, it still can't get it right. The fight for housing in this city is not at 14th and F streets. It's in the neighborhoods. Housing enclaves in commercial zones are an open invitation for more commercial development in residential zones.

The District needs a comprehensive site-review policy, which would require development to be architecturally and aesthetically congruent with neighboring properties and conform to standards that recognize the uniqueness of the nation's capital and the responsibility conferred on those who would build within its historic boundaries. The new mayor should appoint commission members who recognize the crucial role preservation must play in the growth, revival and survival of any great city, especially this one. -- James P. McGrath is chairman of the Citizens' Coalition Against the Proposed Brookings Office Building.