ABSTRACT Researching teacher education often focuses on the content and practices used in training teachers, but rarely focuses on why that particular knowledge or those particular experiences are selected. This paper presents a descriptive framework for investigating the question of ‘why’ in teacher education by exploring sociocultural influences on the work of teacher educators. Beginning with the idea that all educators face dilemmas in deciding what to teach, the framework categorises influences into three domains: the national and local environment, the professional field, and the individual experiences and beliefs. Brief examples in two teacher education contexts serve as illustrations of using the framework in empirical research. The framework presented is applicable across different teacher education content areas and contexts, for both researchers studying the teaching of teacher educators and for teacher educators examining their own practice.