Femtofarad changes in cell capacitance associated with exo- and endocytosis have been recorded. These measurements have generally confirmed electron-microscopic evidence of exocytotic vesicle size and have provided direct evidence for the intracellular fusion of secretory granules and a dynamic measurement of membrane trafficking. Since the giga-seal used in the nontraditional technique provides a mechanical seal as well as an electrical and chemical seal, it has been possible to measure the mechanical properties of the cell membrane using as outputs the activation of mechanotransducing ion channels, the stress-induced increase in patch capacitance, and the membrane strain. >