Discourse about sexuality does not take place in a vacuum but is a reflection of the concerns of the time and society in which it exists. Research itself has tended to reflect this, with priorities on what is important depending on what issues seem of most concern at any one time to significant segments of the population. Sex research since the 1960s has been greatly influenced by the growth of what might be called the second wave of feminism, which arose in the 1960s, and by the appearance of AIDS in the 1980s. The erroneous assumption that AIDS was primarily a disease resulting from homosexual exchange of body fluids also gave further impetus for research into homosexuality, research that also benefited from the growing strength of organized homosexuals and lesbians. The same period saw the growth of a mass consumer market eager for information about sexual pleasure. The 1960s and 1970s also saw considerable public experimentation with alternate lifestyles, which was manifested by group sex, the growth of transvestite clubs, the recognition of the widespread existence of sadomasochism, and an awareness of and interest in the varieties of human sexuality. That time period also saw demands by previously ignored groups, such as the physically disabled, for the right to seek sexual pleasure. Many of these forces were at cross-purposes with each other, and the result of ongoing research has not always been to clarify issues but sometimes to make them more complicated, perhaps because there were no simple answers in the first place.