The experiments reported in this article are concerned with three possible explanations for the “declination effect”. This effect causes a later peak in a contour to be perceived as higher in pitch than an earlier peak with the same F0. The three hypotheses assume that the declination effect should be explained as the result of, respectively, (1) a uniform, time-dependent sloping down of the contour, (2) a lowering of the final portion of the contour only, or (3) a time-independent peak-by-peak lowering function. The results of the main experiment, together with those of a follow-up experiment, show that the declination effect is due both to time-dependent down-sloping and to final lowering, but that there is no evidence for a peak-by-peak lowering function. A production experiment, whose aim was to provide the data on which the stimuli in the perception test were to be modelled, preceded the perception experiments.