For more than a century, New York's Lower East Side has been home to hundreds of thousands of working-class and poor immigrants from across the globe. It also has been the nesting place of painters, poets, writers, musicians and other artists; radical socialists and communists; union activists, and other pioneers of counterculture.

Cultural diversity and political radicalism continue to define of the Lower East Side. What is striking today, however, is that real-estate developers, media executives and others have co-opted these characteristics as marketing tools for residential and commercial redevelopment.

In his new book, "Selling the Lower East Side: Culture, Real Estate and Resistance in New York City" (University of Minnesota Press, 2000), Christopher Mele, assistant professor of sociology, examines the phenomenon in which real-estate developers and city officials exploit images of social difference as a means to lure middle-class renters to the historically working-class district.

The neighborhood's current situation-expensive rentals cheek-by-jowl with the few remaining unrenovated tenements-is characterized by Mele as a "symbolic middle-class embrace of the cultural practices of the poor and disenfranchised."

He points to the use of architectural themes and signage, the abundance of new and upscale restaurants, stores, coffee shops and apartments as a gesture toward the area's radical and vibrant past.

"The effect," Mele says, "is to suggest that boundaries do not exist between the neighborhood's increasing exclusivity and privilege, and its remaining pockets of poverty and community resistance."

This rapport between cultural difference, political radicalism and urban development is relatively new. "Until recently," Mele points out, "the Lower East Side remained stubbornly peculiar-the last holdout of difference surrounded by an increasingly homogeneous, middle-class Manhattan."

This, despite the fact that during most of the neighborhood's history, developers and city officials have sought instead to rid the Lower East Side of its association with difference-to "reinvent" it as a middle-class residential community-mostly failed efforts traced by Mele in the early chapters of his book.

"Selling the Lower East Side" takes us back to the late 19th century and weaves together several historical narratives that deepen the reader's understanding of the area's complex mixture of art, politics and real estate.

On the theme of urban politics and policies, for instance, the author explores more than a century of housing and social reforms, government intervention in rebuilding efforts, urban renewal, cynicism and decline. He also traces the succession of immigrant enclaves on the Lower East Side.

His examination of the past introduces, as well, the multifaceted roles played by bohemians, beatniks, hippies and punks in the course of struggles between tenement dwellers, developers and urban officials eager to eradicate the area's working-class and ethnic identity.

While most of them were of middle-class background, these individuals identified with the politics and culture of the immigrant and the disenfranchised. Although their subcultures aligned themselves with locals, Mele argues that their romanticization of the "other" often reproduced the very same neighborhood images that locals had long sought to resist.

He says the influence that these assorted subcultures had on the area's development represents crucial, post-World War II changes in the production, distribution and consumption of popular culture, which slowly incorporated the Lower East Side and turned it into a "site of social differences" whose mixture of exotic, artistic, marginal, radical and historic elements could be marketed.

Mele argues that today's Lower East Side is changing because the information-based, symbolic economy has produced new opportunities for its exploitation by "place entrepreneurs." Instead of displacing the area's long-held "offbeat" or rogue reputations, these entrepreneurs-often developers-are finding new ways to put associated images of difference and diversity to profitable use.

Their efforts to "reinvent" neighborhoods now involve appropriating, packaging and marketing their identities as a means of accumulating profits in the local real-estate market.

Today visitors can sign up for a $10, four-hour "radical walking tour" of sites connected to various 19th and 20th century activists. They can visit the interactive tenement museum to "meet" the destitute families that occupied these structures and "learn about all facets of the immigrant experience" through videotaped oral histories and photographic exhibits.

For Mele, this stage in the neighborhood's history means new and daunting challenges to the traditional means of local resistance for residents and community groups.

"After all," he says, "much of the Lower East Side's cultural and political identity was borne in the struggles between tenants and landlords, workers and factory bosses-battles over issues of who occupied the margins and who controlled the center, conflicts between the excluded and the privileged. "

Recent efforts to commodify these differences threaten to swallow up those traditions, ignore the significant social, economic and cultural issues at their core and replace them with neat, sanitized versions, all wrapped up and ready for sale."