Analysing the motion of a driven, damped pendulum as a function of the amplitude of the driving force, we show, first, that for moderate values and larger of the amplitude, deviations from a simple motion with the period of the driving force are bounded by a constant times the inverse square root of the amplitude, for late times. For amplitudes above a larger threshold we are able to show that, for late times, the motion becomes a periodic motion with the period of the driving force. The manner in which this periodic motion is achieved with the passage of time is analysed.