The genetic variation for seed yield losses and the response to selection for reduction of such losses was studied by a six-week delay in the timing of harvest in various segregating populations from four lentil crosses. The bulk segregating populations had previously been subjected to different numbers of selection by means of a delayed harvest. The loss in seed yield from a delayed harvest in the two seasons 1981/82 and 1982/83 accounted for 551 and 105 kg/ha seed, representing 34 and 11% of the yield from a correctly timed harvest respectively. Pod drop accounted for 65% of this loss, whereas dehiscence gave 35% of the loss in both seasons. The parents of cross 4 differed significantly for pod dehiscence, with genotype 74TA 550 showing relative indehiscence. Selection by means of a delayed harvest of bulk populations decreased pod dehiscence, mean seed weight and bulk mean yield.