The dynamics of cell morphology, in particular membrane blebbing, was studied after induction of apoptosis by etoposide or camptothecin in four human stabilized cell lines (Hep2, Bowes, HT-29 and HL-60). Time lapse videomicroscopy and F-actin staining revealed various dynamic parameters of this process including its duration, maximal extent, stages and final endpoints in individual cells. Although generally occurring in predictable patterns, our results indicate a relatively significant variability both in appearance and temporal organization of blebbing not only between different cell lines but also within them.