"Metro Center," the proposed hotel, department store and office complex along G Street, between 11th and 13th, promises to do for Washington's forlorn central business district what Rockefeller Center has done for mid-town Manhattan.

It promises to help make downtown look and feel like downtown.

This is not to say that it will dominate the skyline like the Rockefeller towers. This is the nation's capital. It is distinct from other, mostly look-alike American cities, by subordinating commercial self-advertising to respect for history and the majesty of government. Only the Washington Monument and the Capitol stand out.

The special quality that Metro Center's designers are striving to bring to their almost-three-block building complex is not a sense of awe, but a sense of excitement. They would make their impact not in the sky, for the beholder (who seldom looks up, anyway), but on the street, for the participant (who is to be drawn into the bustle).

A sense of excitement -- or call it stimulation -- is best generated by focusing on people rather than "facilities." What interests people most is 1) other people; 2) a variety of things to buy, eat, look at, enjoy and participate in; 3) surprise -- it gets dull when you know what to expect; and 4) a pleasant setting.

The Metro Center design team -- architects David M. Childs of Skidmore, Owings & Merrill and Melin Mitchell, working with developers Oliver T. Carr Jr. and Theodore R. Hagans -- to achieve this by making their complex a monolith, as it were, and then carving amenities and surprises out of it. The unity of the architecture enforces the sense of place. That is what makes Rockefeller Center so special.

All along G Street there will be a shopping arcade of varying height. Building corners will get lively, inviting treatment. There will be a bridge across 12th Street to link the hotel and department store -- perhaps a kind of Ponte Vecchio lined with boutiuqes.

The entire complex, which includes underground parking for 724 cars, is to be penetrated by interior pathways as well as several connections down to the Metrorail station.

The first of the Center's buildings, at the northeast corner of 13th and G streets, now a parking lot, will contain offices. Its neighbor to the west is the frisky little Church of the Epiphany. It will not look hemmed in if the designers achieve what they are after, but rather protectively and respectfully enclosed and endowed with a "close," a quiet open air vestibule often found beside old cathedrals.

The long block between 13th and 12th streets will accommodate the new Hecht's downtown store in the lower four stories. Above them will be six stories of offices. The Washington Project for the Arts, now located there, will join several galleries at D and 7th streets, a neighborhood that wants to become Washington's new art quarter.

To break up the massive effect of this blockbuster, give the offices light and air and emphasize the distinction between department store and office warren, the building will dramatically recede above the fourth floor. This will create a fairly large terrace that cries out for some pleasant outdoor use -- a garden restaurant, perhaps.

The third building, the 450-room Hilton hotel, will feature the bridge and, along 12th Street, a kind of urban open space of which we have little in Washington. The backdrop for that space will be the facade of the fire house of D.C. Engine Co. No. 2, an intriguing relic. The designers will gently slope this paved plaza in hopes that it will be used like a theater for performance and festivities.

The color and facade treatment of the complex are still under study. It is going to be clad in stone, perhaps a pattern different color stone, have plenty of windows and should make the building look lively but not noisy. The written design objectives say: "Make the design distinctively downtown Washington."

What's distinctly downtown Washington?

I suppose it is the tone set by the eclectic, richly decorated commercial buildings that prevailed in the first two decades of this century. Their style range from Louis Sullivan, and his bold towers of brick arches, to Daniel H. Burnham, and his swash-bucking Beaux Arts.

For too many years only the pigeons and a few of us architecture buffs paid much attention to these buildings and they were badly negelected. Between battered and mis-used 19th-century houses, the later "modern" glass-and concrete panel-packaged structures and the parking lots, they lost their influence. There are not enough of them left -- if ever there were enough in the first place -- to impart their distinction on Washington's downtown.

So architect David Childs and developer Oliver Carr, I fear, have the frightfully exhilarating responsibility to create a distinction of their own, to lead rather than follow.

Luckily, we now have a clear idea of what we want a lively downtown business district to be and to look like. Recoiling from Rosslyn and White Flint, we have a new vision of a livable, lively city "where lovers can meet," as Lewis Mumford once put it.

This vision has been thoughtfully and realistically spelled out in a report by the Greater Washington Board of Trade, published two months ago. It is entitled "Downtown: A People Place" and was developed under the direction of Oliver Carr with the help of David Childs, among many others. Within the bureaucratic restraints of a less than daring city administration, Carr and Childs now have their chance.

The fine arts and planning commissions have given their approval. Construction is scheduled to start in December.

As they refine their hopes and designs for Metro Center, the design team will in particular remember the report's injunction that "arts and culture are important economic tools in the revitalization of downtown . . ."

Rockefeller Center owes much of its success to the sculptures, murals, reliefs, fountains and artifacts that adorn it inside and out. None of them is overly distinguised in itself. Together they add up to what is probably America's greatest work of urban design.

Metro Center could do as well.