Sera from 231 women were used to examine their frequency of precipitation of various herpes simplex virus type 1 and 2 (HSV-1 and HSV-2) proteins and to determine if there was a rank order of immune responsiveness of humans to these HSV antigens. Radiolabeled viral proteins were reacted with serum and immune complexes isolated with staphylococcal protein A. Individual antigens were resolved by polyacrylamide gel electrophoresis and visualized by fluorography. As a group, these sera precipitated 31 HSV-1 and 27 HSV-2 proteins. HSV-1 polypeptides with molecular weights of 133,000, 99,000, and 82,000, as well as HSV-2 polypeptides with molecular weights of 131,000 and 101,000, were precipitated by essentially all sera that contained antibodies to HSV-1 and HSV-2. When attempts were made to order the viral proteins by constructing precipitation profiles ranking the antigens in patterns according to their frequency of precipitation, it was observed that the antigens were generally not ordered. Demographic analysis of the sera suggested that the differences in the number of proteins precipitated were associated with differences in age, education, age at first marriage, and income, which collectively may reflect the frequency of exposure to the virus.