This paper explores the ways in which women and men use language to mark gender boundaries, and to convey femininity and masculinity in the construction of a gendered identity. The first section of the paper examines evidence that language serves as a gender identity marker not only in the particular phonological variants used more by women than by men, but also in the wider stylistic range evident in women's discourse in some communities. The gender distribution and social meanings associated with particular pragmatic particles and interactional devices provide another indication of the ways in which women and men construct and express femininity and masculinity in interaction. The final section analyses the construction of stereotypical gender identities through conversational interaction, firstly by means of a narrative and secondly through the carefully crafted dialogue of an advertisement. The paper demonstrates the complementary nature of macro-level quantitative studies and qualitative ethnographic analysis in gender research.