An enzyme immunoassay was used for the rapid detection of herpes simplex virus type 1 (HSV-1). The test utilized specific antibodies to HSV-1 attached to a solid phase. A laboratory preparation of HSV-1 was detectable in amounts of greater than or equal to 50 50% tissue culture-infective doses by this method. Tests performed with clinical samples indicated a specificity of 95%. The sensitivity appeared to depend on the length of time the samples were stored. When samples were stored frozen for three to six months, the sensitivity was 46% of that of tissue culture isolations performed when the samples were first collected. The sensitivity was 89% in comparison with attempts at tissue culture reisolation with the same samples at the time of enzyme immunoassay. The immunoassay also detected HSV in seven of 10 positive samples that were stored frozen for no more than two weeks before testing.