Judging from current progress in nanoscale imaging and cutting, histochemical and genetic methods for staining, and computational algorithms for image analysis, it should soon be possible to create automated systems that will take a sample of brain tissue as input and generate its “connectome,” a list of all synaptic connections between the neurons inside. Such systems will give rise to a new field called “connectomics,” defined by the high-throughput generation of data about neural connectivity, and the subsequent mining of that data for knowledge about the brain. I will discuss the possible impact that connectomics could have on our understanding of how the brain wires and rewires itself, the dynamics of activity in neural networks, and the neuropathological basis of mental disorders.