Dr Richard Kingston and Dr Bryan Marshall provide a critical view on smart cities and discuss some of its implications to rethink the role of citizen engagement in urban and transport planning. One of the core ideas behind Smart Cities is that the progress in information technologies enables urban and transport planning to be based on better informed decisions using data-driven solutions to urban problems. Yet our understanding of how the emerging role of technology and data in our cities will shape public participation in urban and transport planning is still limited. A well-discussed pitfall is that smart city technologies can give the false idea that urban planning becomes simply a matter of efficient administration, leading to technocratic approaches in decision-making. Despite the potential of such smart technologies to engender new forms of public participation and reduce information gaps between citizens and local governments, another pitfall is that not all social groups equally have the appropriate skills and resources to use these new technologies to influence planning decisions. In both cases, an uncritical adoption of smart cities can undermine participatory planning, either by withdrawing the political and participatory dimension of planning, or by exacerbating the social imbalance of who gets to be heard. This seminar will provide critical view on smart cities and discuss some of its implications to rethink the role of citizen engagement in urban and transport planning.