A new method has been developed to study the effects of vibration environments upon human beings. The method is usable to assess the effects of random vibration, transients, or sinusoidal wave forms. It is equally effective for synthesis or analysis of applied force, effective mass, impedance, displacement, or acceleration. The linearity of human response to vibration is established. The procedure employs the transfer function technique. Data are presented describing human response to vertical motion for voluntary tolerance and low intensity acceleration. The frequency spectrum studied was 1–60 cps.