An indirect enzyme-linked immunosorbent assay (ELISA) with a mixture of eight different gonococcal outer-membrane proteins (OMP) as coating antigen was evaluated for detection of gonococcal antibody in 507 sera obtained from patients selected from high-risk and low-risk populations. The indirect ELISA method was more specific and sensitive when the polyvalent antigen was used than when OMP from only one serotype was used. Past episodes of the gonorrhoea had a significant influence on the seropositivity of the test. In a selected low-risk population the specificity of the assay was 94% and in a selected high-risk population the sensitivity was 78%. When sera from 24 asymptomatic individuals were tested the sensitivity was 83%. The ELISA polyvalent-antigen test should be useful as an aid for the detection of gonorrhoea in populations with a low prevalence.