Frank Williams, a native of California, may just be the quintessential New York architect. He moved to the city three decades ago and in that time he has built more than 20 of the tallest structures in Manhattan, with another one just announced at 176 Madison Avenue, near 36th Street. In fact from the window of his apartment in a building he designed at 80th Street and Columbus Ave., he can see 12 other buildings he designed, among these the Four Seasons Hotel, Trump Place, and 515 Park Ave.

He is a typical New York architect in another sense, however: Thus far, he has subsumed his identity in his buildings, an essential New York attribute as regards architects. Here natives tend not to care, think about, or even realize that the buildings that hem them round — with rare exceptions such as the Guggenheim Museum — were actually designed by someone in specific, rather than being anonymous acts of God, like the sequoias of Mr. Williams’s native California.

Although Mr. Williams began his career squarely in the modernist camp, as can be judged from the massing of the Columbia at Broadway and 96th street, a brick structure with jarring Brutalist cantilevers, he really came of age as an architect of classical postmodernism in the mid-1980s. A key concept in his architectural vocabulary is what he calls “New Yorkism.” By this he means an evocation, hard to quantify or pin down, of those qualities that cause a building to look simply correct in the context of the New York skyline. These are the same qualities that would cause Chicago’s John Hancock Building to seem out of place in Manhattan and the Chrysler Building to seem out of place amid the skyscrapers of San Francisco’s downtown.

Aside from the quality that Justice Stewart once defined as, “I know it when I see it,” this New Yorkism can be seen as non-dogmatic historicism. Thus it partakes of neither the more rigorous historicist reconstruction associated with architects such as Peter Pennoyer, nor the laissez-faire classicism of Michael Graves. At the same time, this New Yorkism is more committed to imposing a historicist narrative on its façades than are the projects of Robert A. M. Stern, which appear by turns classicizing or modernist or something else in obedience to their context.

Mr. Williams tends to favor masonry cladding, usually pale granite or limestone, with punched windows of the sort that are typical of New York buildings from the first two great ages of skyscrapers in Manhattan, around 1900 and around 1930. These stand in stark contrast to the curtain walls of International Modernism, which dominated the third age of New York skyscraper construction, in the postwar years, and continue to dominate it today. Finally, they favor a tripartite division into base, shaft and lantern, that rejects the modular regularity of mainstream modernism and that was a staple of skyscraper construction from Louis Sullivan to Raymond Hood. And now Mr. Williams returns to New York — after several years of building abroad — to work on a project, a 35-story boutique hotel and residential tower, 176 Madison Ave., whose newly released rendering appears to contradict the bent of his activities thus far. Surely the architect has not gone the way of Deconstruction, but he shows a greater and more saleable respect for Neo-Modernism than he did in the past. Like all his buildings, this latest appears to be a whitish tower, but now that pallor is achieved with a curtain wall rather than with masonry cladding. At the same time, it divides into a traditional base with a recessed central zone on three sides, from which springs a setback shaft.

At the summit sit the expected lantern, covered not in the classicizing limestone of 515 Park Ave., however, but rather in a series of interlocking glass planes that do indeed have — when all is said — a touch of Deconstructivism to them. In fact, they were informed by the treatment most recently favored in Renzo Piano’s newly completed Times Tower. For all that, the project promises, when completed, to fit collegially into the skyline of New York, as do Mr. Williams’s other buildings in Manhattan.

But another project of his presents us with a paradox. This is intended to be an homage to the classic New York skyscraper that Mr. Williams clearly loves, but just as clearly would be out of place in Manhattan. In any case, it was not intended for us, but for Moscow. According to the rendering that his firm has released, Mr. Williams has abandoned the tripartite structure of his New York buildings in favor of a step-like progression of four mounting diagonal thrusts along a curtain-wall, culminating in an antenna that skewers the skyline. Such a dramatic structure would probably not have passed muster with the various review boards in New York, but it succeeds in evoking the grandly histrionic, operatic exuberance that has always been a staple of Russian architecture. Indeed, it may come closer than any other building to realizing Vladimir Tatlin’s aborted dream of a monument to the Third International. But surely it is strange that a New York architect should have been the one to make it a reality!