Local genital antibodies to the infecting strains of Neisseria gonorrhoeae were demonstrated by indirect immunofluorescence (binding antibody) and by their ability to inhibit the attachment of gonococci to epithelial cells (functional antibody). Both IgG and IgA classes of immunoglobulin were involved, and the IgA component were primarily of a secreting (11S) nature. The ability of local genital antibody to inhibit attachment appears to persist for at least a short period of time and to be relatively strain specific.