Dr. Christian Haid is co-founder of POLIGONAL Office for Urban Communication Berlin and senior researcher at Habitat Unit (Technical University Berlin). Christian holds a PhD in urban sociology (Humboldt University Berlin) and is trained in urban studies (UCL London) and architecture (Academy of Fine Arts Vienna). With POLIGONAL he develops communication formats at the intersection of urban practice, art and architecture. At Habitat Unit Christian writes about, researches, and teaches in international urbanism. Urban Informality, transformative city planning, postcolonial urbanism, and the politics of public space are his main interests.