It is not uncommon for existing buildings to be very close, if not adjoining, to each other. Without any separation, pounding between adjacent buildings may pose serious seismic hazard. In the case of redevelopment of just one building within the building group, it is desirable to incorporate means of seismic mitigation to the existing buildings. In the past years, seismic isolators have been successfully used to decouple the superstructure from ground motion. It has also been suggested to separate adjacent buildings using dampers to reduce the adverse effect of pounding. In this study, inter-building dampers are used to connect the buildings to reduce the effect of pounding and base isolators are installed in the new building to reduce the effect due to ground motion. Equations of motion are formulated to represent the response of a building group to strong earthquake motion. Parametric studies are performed to assess the impact of varying both stiffness and damping of the inter-building dampers to the building group. As compared with the case of without inter-building dampers, structural response of the existing building is reduced.