I have been invited to a conference this winter in St. Petersburg, Russia, to talk about "Architecture and the Global City." I may be the odd man out at the conference, titled "New Global History and the City." Most invitees are slated to discuss economic, social, cultural, political and historical issues related to the contemporary phenomenon of globalization and urban evolution.

I, on the other hand, will discuss the fast food factor -- the McDonaldization of architecture.

Many of us love to visit character-laden cities such as St. Petersburg, Paris, Rome, Venice, Agra and Bangkok, or wander through picturesque towns and villages in Tunisia, Greece, Spain, Mexico and Japan -- or, for that matter, in the United States. Much of what appeals to us about these places is traditional architecture that is locally distinct. We admire historic buildings, neighborhoods and communities shaped by site, climate, history, native culture and locally available materials and construction technology.

But are such unique places at risk of being engulfed by the rise of "global" cities that eventually could look more or less the same, full of buildings that could be anywhere? Is architecture becoming increasingly globalized, standardized, sanitized?

Two opposing forces affect architectural globalization.

One force seeks to safeguard and promulgate established indigenous architectural traditions, forms, decorative motifs and technologies. It advocates historical continuity, cultural diversity and preservation of geographic identity, all symbolized by a particular architectural vocabulary, just as spoken languages and local dialects impart identity.

The other force promotes invention and dissemination of new forms using new technologies and materials in response to changing functional needs and sensibilities. It places a premium on systematization, flexibility and interchangeability. As commerce, transportation, communication and information become globalized, it argues for internationalized, innovative architecture transcending local conventions and constraints.

The tension between anti-global and pro-global forces has long existed.

Architectural history is filled with movements opposing cultural and aesthetic diversity while sanctioning particular philosophies of architecture for national and international distribution.

Pro-global design sponsors include governments using architecture to symbolize the state, companies employing architecture for corporate and product identification, and zealous, sometimes self-righteous architects preaching their own theories.

The ancient Romans established the first example of global architectural hegemony, spreading their ideas across the empire. Rome didn't completely suppress indigenous architectural practices of the provinces, but Roman classicism nevertheless was the empire's ubiquitous architectural theme, one that is still popular today.

In the early 20th century, many European and American architects rebelled against classicism and neoclassicism. They argued stridently that the modern age demanded new architecture in response to new industry, technologies, mobility, and social and political orders. Thus was born the "International Style," with German emigre architects Mies van der Rohe and Walter Gropius as the leading prophets.

The International Style was based on systematization and standardization, mass production, economies of scale, functional logic and aesthetic composition devoid of both ornament and sentiment. Given a similar functional program, the design of a building in southern Asia could be similar to one in South America. For several decades after World War II, International Style thinking greatly influenced the design of office buildings, schools, hospitals, laboratories and multifamily housing.

Today pressures to globalize architecture primarily spring from two sources: the culture of commerce and the culture of design.

The global culture of commerce is driven by changing consumer expectations, market opportunities and business agendas. Their architectural manifestations include iconic, skyscraping banking towers (often built where they don't belong); chains of standardized hotels and franchise restaurants and shopping malls full of all-too-familiar name-brand stores.

Yet wouldn't you expect to find these in a city that called itself "global?" Aren't you likely to feel more comfortable in a hotel room like others you have stayed in, perusing a menu with foods you recognize, or shopping in a store with merchandise like the store at home? The experience of strolling through malls at Canary Wharf in London's Docklands, at Potsdamer Platz in Berlin and at Manege Square in Moscow is fundamentally the same.

The global culture of design is supported by architects who study what other architects are creating, no matter where. With fabulous photographs in slick magazines and professional journals, trend-conscious designers can scan and span the globe, sharing high-style concepts rendered in stylish materials. Glass, aluminum, stainless steel, copper, titanium and natural stone are readily available. If they can't be acquired locally, they can be imported.

Thus it's not unusual for a building in New York or Shanghai to be constructed with a sophisticated glass and metal curtain wall made in England or Germany and granite and marble imported from Spain or Zimbabwe.

Once this would have been considered prohibitively expensive, but today shipping materials globally has become routine.

In the world of architecture, the struggle between globalizing and anti-globalizing forces will continue, as it has for centuries. Yet I'm betting that, even a hundred years from now, cities such as Paris, Rome, London and St. Petersburg will still retain their traditional architectural allure and still be worth visiting, regardless of which force prevails.