In this study, the profile and practices of subject discipline teacher educators are examined, providing possibly the first investigation of this cadre of a teacher educator. The subject discipline teacher educator is a subject specialist involved in initial teacher education, for example, a physics lecturer teaching on an initial teacher education science course. The subject discipline teacher educators studied work in concurrent (post-primary) initial teacher education in Ireland. More than half of the teaching and learning experiences of student teachers on these courses happen within their subject discipline. Despite the considerable exposure of student teachers to subject discipline teacher educators, very little is known about this group. In a survey of 70 subject discipline teacher educators, several factors related to their profile and practices were analysed. The results indicate that subject discipline teacher educators are a distinctive group of teacher educators, committed to, and engaged in the practice of teacher education.