Tonight IAAC welcomed Peter Trummer lecture “From the city as a filed to the city as an object” within the Winter IAAC Lecture Series. The lecture unfolded the relationship between urban planning and urban design. A disciplinary knowledge that ones was united and was invented by Ildefonso Cerda and his Theory of urbanization. Urban planning is understood as the regimes that form the knowledge on which urban decisions are based on. This can span from administrative to legislative to economical and technical ones. Urban design is understood as a material projection on which urban environments are formed and shaped. The lecture shown the shift within the discipline of urban design form understanding cities as a field problems towards a the understanding of cities as objects.