Science teacher professional development is complex. Phases in a teacher's career necessitate different professional learning opportunities. Furthermore, knowledge bases, practices, and attributes need to be cultivated during these times. For science teachers, it is not always evident how to link professional learning opportunities progressively toward different outcomes, including being a department head, teacher leader, curriculum developer, or even master teacher. In order to spur a discussion about purposeful teacher learning, we use a theory of transformative learning to examine research pertaining to the professional learning of science teachers. The result is a conceptual framework that suggests that teachers should build their knowledge, practices, and attributes in a way that allows them to realize their potential within specific communities. This framework acknowledges that teachers change over time; that knowledge, practices, and attributes are involved in these changes; and that the situated positions of teachers contribute to these changes. Examples associated with this framework are shared in the article to enable educational researchers to approach the study of science teacher development in different ways, which can help guide professional development programming, teacher learning, and potential policy decisions. Most important, this framework offers science teachers a way to consider their own professional growth.