Sandy soils behave nonlinearly at stress levels below the peak stress. This influences the dynamic response of the foundations built on sandy soil. This paper shows first the nonlinear vibration response of a block-type foundation due to the vertical, horizontal, and rocking excitations. The nonlinear vibration responses are compared with the linear response assuming linear soil behavior. The second part of the paper shows how to control the harmful effects due to the nonlinear vibrations using passive and active control mechanisms attached to the foundation.