In reviewing the development of competency-based teacher education, emphasis was placed on philosophical and psychological rationales and on systems analysis. The philosophical rationale stresses the acquisition of knowledge in teacher education programs. Competency-based teacher education programs broaden this scope to include the application of this knowledge to actual learning situations. The psychological rationale stresses the manner in which individuals learn, as well as behavioral objectives. The concern for behavioral objectives provides the impetus to specify and measure specific learning outcomes. Systems analysis emphasizes the purpose, process, and components of teacher education. Competency-based teacher education programs also broaden this spectrum to include the necessity of evaluation in the program. Further research is needed. (Thirteen references are included in the paper.) (BRB)