Bogotá, Colombia’s , Doris Salcedo is a part of the Guggenheim’s current show, Contemplating the Void. For the exhibit, which marks the building’s 50th anniversary, nearly two hundred artists, architects, and designers were invited to imagine their dream interventions in the rotunda of the space. Her mash- up art piece combines a downward view of the rotunda with a photograph of a New York tenement by the German-born artist Hans Haacke. The tenement photograph, part of his series documenting the holdings of a local real-estate baron, was scheduled to be featured in the 1971 Haacke show at the Guggenheim that was canceled for what were widely believed at the time to be political concerns by the museum’s director.

“What Hans was doing was amazing, and it was censored,” said Ms. Salcedo, a sculptor who is also politically inclined. She wrote to Mr. Haacke to obtain his image and then worked with four architects over several months to create the perfect alignment with the other picture. “It was a nightmare in Photoshop,” she said.

Her point is not so much an institutional critique as a take on the power of design, good or bad. “Architecture has a real effect on us,” she said. “The lack of architecture in the ghetto has a real effect on the people who live there.”

In another of her works Shibboleth sets out to intervene directly with the fabric of Tate Modern’s Turbine Hall. Rather than fill this iconic space with a conventional sculpture or installation, Salcedo has created a subterranean chasm that stretches the length of the Turbine Hall. The concrete walls of the crevice are ruptured by a steel mesh fence, creating a tension between these elements that resist yet depend on one another. By making the floor the principal focus of her project, Salcedo dramatically shifts our perception of the Turbine Hall’s architecture, subtly subverting its claims to monumentality and grandeur. Shibboleth asks questions about the interaction of sculpture and space, about architecture and the values it enshrines, and about the shaky ideological foundations on which Western notions of modernity are built.

In particular, Salcedo is addressing a long legacy of racism and colonialism that underlies the modern world. A ‘shibboleth’ is a custom, phrase or use of language that acts as a test of belonging to a particular social group or class. By definition, it is used to exclude those deemed unsuitable to join this group.

‘The history of racism’, Salcedo writes, ‘runs parallel to the history of modernity, and is its untold dark side’. For hundreds of years, Western ideas of progress and prosperity have been underpinned by colonial exploitation and the withdrawal of basic rights from others. Our own time, Salcedo is keen to remind us, remains defined by the existence of a huge socially excluded underclass, in Western as well as post-colonial societies.

Here is another one of her magnificent works she did for the Istanbul Biennial in 2003.