This paper examines the proposition that languages may differ in their potential for non-sexist usage, and that the structure of a language, in particular the gender system, affects the nature of the linguistic response to changing social attitudes regarding sex roles. A brief historical survey of gender and sex-marking is followed by a review of the situation in several languages including contemporary English. It is concluded that the structure of a language is one factor influencing the rate of linguistic change in response to social change and that, while the sex-based system of English does not present a serious obstacle to language change, the grammatical gender of some languages may constitute an impediment to change. It is also hypothesized that, as pressures for social change make speakers aware of the sexist implications of the gender system, the purely grammatical and the sex-based criteria will come into conflict, introducing instability into the system. Data from several languages are presented indicating the presence of such instability, especially in words denoting professions and other social roles, and some tentative predictions are made regarding future developments. (Author/AMH)