The design and implementation of a nonlinear model predictive controller (MPC) scheme for an energy efficient office building is presented. Because of the nonlinear building behavior local linear model networks are used to model the building dynamics. For each of the building's zones a dedicated Fuzzy model predictive controller (FMPC) is implemented. In addition to the FMPCs a global MPC is designed to control the coupling zone (concrete core activation). To coordinate the overactuated system a cooperative iteration-loop is designed, which leads to cooperative Fuzzy model predictive control (CFMPC). The CFMPC has been successfully implemented in a real office building, and the first results after commissioning are presented and discussed. Additional simulation studies demonstrate that the proposed CFMPC achieves higher comfort with less cost as compared to a rule-based controller. (C) 2017 Elsevier B.V. All rights reserved.