"The statistics given throughout this volume on the incidence of homosexual activity, and the statistics to be given in the present section of this chapter, are based on those persons who have had physical contacts with other males, and who were brought to orgasm as a result of such contacts. By any strict definition such contacts are homosexual, irrespective of the extent of the psychic stimulation involved, of the techniques employed, or of the relative importance of the homosexual and the heterosexual in the history of such an individual. These are not data on the number of persons who are “homosexual,” but on the number of persons who have had at least some homosexual experience. . . . In these terms (of physical contact to the point of orgasm), the data in the present study indicate that at least 37 percent of the male population has some homosexual experience between the beginning of adolescence and old age. This is more than one male in three of the persons that one may meet as he passes along a city street. Among the males who remain unmarried until the age of 35, almost exactly 50 per cent have homosexual experience between the beginning of adolescence and that age. . . . These figures are, of course, considerably higher than any which have previously been estimated. . . . We ourselves were totally unprepared to find such incidence data when this research was originally undertaken. Over a period of several years we were repeatedly assailed with doubts as to whether we were getting a fair cross section of the total population or whether a selection of cases was biasing the results. It has been our experience, however, that each new group into which we have gone has provided substantially the same data. Whether the histories were taken in one large city or another, whether they were taken in large cities, in small towns, or in rural areas, whether they came from one college or from another, a church school or a state university or some private institution, whether they came from one part of the country or from another, the incidence data on the homosexual have been more or less the same. . . ."