As an alternative to the usual procedure, it is suggested that theoretically exact dwells are not demanded from cams so that a single motion law to cover the entire cycle and its repetitions can be prescribed, thus avoiding sudden changes in the motion derivatives of all orders. A way is shown to arrive at such a motion law for dwell-rise-dwell cams with freedom to optimize for kinematic or dynamic characteristics. Unequal top and bottom dwells as well as unequal rise and fall times can be obtained. The use of a finite trigonometric series to cover the entire motion cycle enables direct control over high frequency components of the motion. Calculations for the case of unequal rise and fall times can be reduced, if the finite trigonometric series is sacrificed. Numerical evidence is included. © 1987.