The phenomenon of hypergraphia, or the tendency toward extensive and, in some cases, compulsive writing in temporal lobe epilepsy is described in seven patients, in each of whom there was electroencephalographic demonstration of a temporal lobe focus. Unusually detailed and strikingly copious writing was evidenced in each patient. Six patients provided documentation of their extensive writing, which often was concerned with religious or moral issues. A seventh patient claimed to have written extensively, but refused to exhibit his writings. Aggressiveness, religiosity, and changes in sexual behavior in temporal lobe disorders have been described previously. The hypergraphia of temporal lobe epilepsy appears to be part of a specific behavioral syndrome of special interest because of its association with dysfunction at specific anatomic loci.