From 24th September 2009 to 10th January 2010, the 2009 Rotterdam International Architecture Biennale (IABR 2009) will be held at the Nederlands Architectuur Instituut. This is a biennial architectural event which on each occasion focuses on a different theme. This year it is ‘Open City: Designing Coexistence’. In one of the exhibitions, entitled Maakbaarheid (Social Engineering), nine Rotterdam projects will be shown which all in various ways have some connection with this theme. Hofbogen is one of the nine. In association with the deputy curator of the exhibition, Crimson Architectural Historians, the Hofbogen project office, Vestia Noord and the Zomerhofkwartier project group commissioned the French architectural firm Atelier Seraji to draft a design outline for, among other things, two development areas directly adjoining the Hofplein viaduct, these being the neighbourhood around the De Punt building in the Bergweg district, and the Zomerhof district. The purpose of this brief is to examine ways in which both spatial and programmatic interaction is possible between these areas and the Hofplein viaduct. The design signifies a further substantive expansion of the scenario that Hofbogen had previously presented in the Toekomstvisie De Hofbogen, het langste gebouw van Rotterdam (A Vision for the Future of the Hofbogen, the longest building in Rotterdam). The products of this design brief can be seen in the main IABR exhibition at the NAi.