Concrete placing booms are subjected to vibrations that increase mechanical stress and reduce the boom’s working life. The aim of this paper is to develop an active control methodology to suppress boom vibrations using the same actuators that produce the large motion of the boom. The control logic is based on two contributions, a feedforward and a feedback one. In this study, a nonlinear flexible multibody model was created to simulate the boom’s dynamic behavior. This model was also used to develop and test the control logic. Finally, the control methodology was validated on an experimental test rig.