A detailed study has been conducted on the effect of different types of variation in profile and thickness on the amplitude and the dynamic bending stress of a beam under a point harmonic load. The end conditions considered are clamped or simply supported at both the ends. The response has been calculated for the first three modes of vibration. In each case the results obtained for different types of thickness variation are compared with those obtained for a uniform thickness beam. It is observed that a considerable reduction in amplitude and bending stress can be achieved by proper selection of thickness variation. © 1993.