In this paper, a mixed passive-active control strategy to mitigate the seismic response of a three-building system is presented. The proposed strategy combines passive dampers, placed as inter-building linking elements, with local active control systems implemented in those buildings that require a higher level of seismic protection. Different active-passive control configurations are considered, which may be suitable for different levels of seismic protection and combine the high performance characteristics of active control systems with the simplicity, reliability, and low cost of passive control elements. The numerical simulations carried out to assess the performance of the proposed methodology indicate that the buildings vibrational response and the risk of inter-building pounding events may both be effectively mitigated by means of a proper active-passive control configuration.