Variations in agglutinin titers against S. mutans were larger in women than men, but since no systematical variations are recognized during menstrual cycles there is at least no simple way of relating these variations to the titers of the sampling technique. The titers of the salivary agglutinin studied do not seem to follow a regular pattern. To obtain an appreciation of the general level of concentration and variability for an individual, several saliva samples have to be analyzed over a longer period of time.