Cover legend: Illustration of a serially reconstructed GABAergic synapse on a hippocampal pyramidal call that is labeled for neuronal nitric oxide synthase (nNOS; black particles on the postsynaptic side of the synapse). The image is a three-dimensional rendering, but the serial-section surfaces are taken from real electron micrographs of nNOS-labeled sections. For more information, see the article by Szabadits et al. in this issue (pages 8101–8111).