The purpose of this study was to suggest the strengthening strategies of key competencies needed for the workforce. Concretely, this study was intended to suggest to strategies for educating key competencies and for supporting the education of key competencies in the elementary and secondary education. For accomplishing these objectives, literature review, analysis of the cases in the developed countries, and expert committee were used. The results of this study were as follows: First, we proposed the educational objectives, contents, methods of instruction and learning, and evaluation methods for educating key competencies in each area of competencies. Also, we investigated the relationship between key competencies and national core curriculum in order to suggest possible strategies for the infusion of key competencies into the national core curriculum. Second, we proposed the strategies through the establishment of new subject, `Human and Vacation for educating key competencies. Specifically, we suggested educational objectives, contents, plan of instruction-learning, and plan of evaluation of this subject. Third, for supporting the education of key competencies, this study proposed the following strategies; the reinforcement of teacher education arid in-service training, the development and diffusion of curriculum and educational materials,, the improvement of legal and institutional systems, the change of social consciousness on vocational education, and the assistance of research and development. Based upon the results of this study, some recommendations for policy execution and further research were suggested.