If teachers are to adequately support development of their students' numeracy capabilities then they need to have an identity as a teacher of numeracy. A preliminary evaluation of a conceptual framework (Bennison & Goos, 2013) developed for use in a two-year study that seeks to understand this construct is presented. Initial findings about an early career secondary science teacher are utilised to describe this teacher's identity as a teacher of numeracy, enabling the conceptual framework to be illustrated and critiqued.