Sera from 1,167 individuals were tested for antibody to Neisseria gonorrhoeae by use of five different serologic tests. These were complement fixation, the indirect fluorescent antibody test, Gonosticon Dri-Dot, fluorescent gonorrhea test-heated, and gonorrhea screen test. Parallel cultures of material from the throat, urethra, cervix, and rectum were also done. The results were analyzed by a technique intended to separate test effects from population effects. Test specificities ranged from 81.3% for the Dri-Dot test to 96.1% for the indirect fluorescent antibody test. Sensitivities ranged from 55.6% for the Dri-Dot test to 81.5% for the fluorescent gonorrhea test-heated.