This paper is a review of the research literature related to theories of reasoning and teacher thinking. Judgment theory, decision theory, and problem-solving theory are discussed. Reviews are provided for studies from three major research projects on teacher thinking: The Institute for Research on Teaching, Special Study C of the Beginning Teacher Evaluation Study, and Shavelson's Research. Comments are made on the relevance of reasoning theories to what occurs in naturalistic settings, and the need for further research on teacher thinking, especially teacher decision making in special education settings. (Author)