16th- and 17th-century thought about the gendered body was in some respects deeply paradoxical. On the one hand, almost everyone assumed that men and women were very different in capacity and nature, and these differences were enshrined in law including property and marriage law, in religious belief and practice, and indeed at all levels of culture.On the other hand, the 'one sex' model of the body also allowed the possibility that sex and gender were very fluid, changeable, and liminal. This lecture investigates this paradox in relation to representations of physical bodies and physical space. In a number of plays where gender seems peculiarly fluid - in some domestic tragedies like Arden of Faversham, Jonson's Epicoene, Cavendish's The Convent of Pleasure and The Presence, some plays of Behn - spaces are carefully defined to symbolise gender as both fixed and fluid. Thus in Epicoene windows, doors and literal thresholds comically define a world where gender is liminal; in Arden of Faversham Anne's adultery and murder render her femininity questionable, and the play uses images of weirdly equivocal domestic spaces to underscore this; Cavendish attempts to invent feminised spaces where gender differences are deconstructed; and Behn, as Derek Hughes has recently very effectively argued, is very adept in using theatrical space as part of a changing discourse of gender.