The Boston Teacher Residency program is a yearlong, selective preparation route that trains aspiring teachers, many of them career-changers, to take on jobs in some of the city's highest-needs schools. The program, which fits neither of the two most common types of teacher preparation--alternative routes and traditional teacher education programs--is modeled along the lines of a medical residency that pairs classroom training with practical experience. This article describes the benefits of the Boston residency program and explains why districts are turning to this model for preparing effective educators.