<p>Despite its importance for the discipline, the statistical investigation cycle is given little attention in schools. Teachers face unique challenges in teaching statistical inquiry, with elements unfamiliar to many mathematics classrooms: Coping with uncertainty, encouraging debate and competing interpretations, and supporting student collaboration. This chapter highlights ways for teacher educators to support teachers' learning to teach statistical inquiry. Results of two longitudinal studies are used to formulate recommendations to develop teachers' proficiency in this area.</p>