The effect of viscoelastic damping on transfer function characteristics of structures is discussed. Three types of viscoelastic damping treatments were examined: free layer, constrained layer, and constrained layer spaced from the neutral axis. Structures were tested with and without damping treatments for slow sweep and fast transient sweeps at two amplitude levels. The transfer functions were calculated and used for determining the effectiveness of the treatment for reducing the response.Analysis was performed for the modal characteristics, inherent damping, additive damping, and transfer functions. Correlation between the predicted and test transfer function magnitudes showed the acceptability of the analysis method.