The focus of this paper is Jackie Kay’s novel, Trumpet, the fictionalised account of a woman (Josephine Moore) who lives her life as a man (Joss Moody). This paper looks at how Joss’s identity is constructed, as well as the impact this has on the identities of other people. In particular, the paper examines the difficulties faced by Joss’s wife, Millie, as she tries to help him keep his secret, and protect her own identity as a heterosexual wife. Her attempts to defend herself and her husband from accusations of lesbianism lead to an examination of the power of labels and the essay questions both Millie’s commitment to the truth as she sees it and the usefulness of gender labels in determining identity