Architects Elizabeth Diller and Ricardo Scofidio have questioned conventional approaches to spatial temporality and the situation of architecture since the late 1970s. Now joined by Charles Renfro, the installation and architectural projects of their interdisciplinary design studio Diller Scofidio + Renfro are representative of the shift from the aesthetic architectures of post-modernism towards a critical architecture based upon the principles of time-based art. As a reflection on the question of duration and performance, this article returns to Diller Scofidio + Renfro's temporary structure for the Swiss Expo in 2002. Blur Building, or Blur, underlines the occurrence of time through its continuously shifting structure and ephemeral state. Located on a steel-viewing platform on Lake Neuchâtel, Blur was a literal performance of its lakeside site as a series of water jets formed a suspended mist cloud around its steel frame: an ephemeral architecture of water and action. This event-based spatial ecology of Blur is typical of Diller Scofidio + Renfro's focus on the affect of architecture and the social consequence of buildings. Influenced by their initial explorations within a theatrical setting, Diller Scofidio + Renfro integrate the experience of technology and architecture to evoke the social and material contexts of the ‘site’ or situation. Notions of spectatorship and participation recur throughout their architectural interventions, as they aim to position architecture as a means of spatial and haptic revelation: where the event of architectural experience has a direct impact upon our embodied perception of ourselves. Framed by Dorita Hannah's notion of ‘spatial performativity’ and the writings of architect's such as Juhani Pallasmaa and Bernard Tschumi, this article concludes with by reflecting on how Blur is representative of the critical discourses that have shaped contemporary approaches to site and performance, the dramaturgy of architecture.