The theory of evolution is the fundamental backbone to the discipline of biology, yet many students possess misunderstandings. The teacher is the most important school-based factor in student learning, and therefore to improve students' understandings of evolution, we must better prepare teachers. The purpose of this paper is three-fold. First, we reviewed empirical research studies focused on K-12 teachers regarding evolution education from 1993 to 2011 with the purpose of identifying major themes of research and corresponding findings. Second, we used our understandings of current findings to inform the development and articulation of five goals for teacher preparation. Third, we discuss implications of this work for teacher preparation initiatives and directions of future research. We found that current evolution education research specific to K-12 teachers falls within four major themes, which collectively inform the development of five goals for preparing teachers to teach evolution. We argue that teachers should: (1) develop content knowledge of evolution; (2) develop understandings of the nature of science related to evolution; (3) develop acceptance of evolution as valid within science; (4) develop knowledge of and strategies for handling the public controversy; and (5) develop pedagogical content knowledge for teaching evolution. Based on our review, evolution courses and professional development initiatives for K-12 teachers should integrate the five goals, with more attention to teaching evolution in the classroom. Investigating the nature of teachers' acceptance of evolution and pedagogical content knowledge for teaching evolution are areas of research in need of continued pursuit.