Two independent techniques, in situ hybridization on frozen sections and reassociation kinetics, have been used to localize Epstein-Barr virus genomes in tissue samples from healthy human adults. Whereas specimens taken from the palatine tonsils were invariably negative, all samples from the parotid gland were positive when tested with either technique. This observation suggests that the parotid gland is, besides the peripheral lymphocytes, a site of lifelong persistence of Epstein-Barr virus and probably the site of low-level virus production which may be the source of virus found in the oropharynx.