This article describes the development of a comprehensive three-dimensional finite element model for the Stata Center basement excavation (Cambridge, USA) using PLAXIS 3D 2012. The project involved a complex sequence of berms, access ramps and phased construction of the concrete mat foundation. Lateral wall movements and building settlements were closely monitored throughout construction, while photos from a network of webcams located around the open-plan site provided a detailed time history of the construction processes. The analyses highlight the effects of the 3D excavation and support geometry on wall deflections and show a good agreement with the measured response assuming undrained conditions using the Mohr-Coulomb soil model.