The aim of this article is to review the experiences of educational systems of different countries on using a competency-based approach (CBA) in their secondary schools. The historical development of CBA and the roles of using this approach in teaching and learning are also reviewed. Consequently, 8,296 published scholarly papers, books, reports and documents between 1985 and 2017 were found in the English language. The 14 selected articles from 2012 to 2020 have been revised and categorised based on the year of publication, country, purpose, method of study, sample and findings. Results of this review paper indicated that CBA can be a great approach to improve the teaching and learning process if teachers could reduce the barriers of its implementation. Therefore, this study recommends helping teachers in this matter through training and providing all needed resources, and then examining the new situation by future studies.   Keywords: Competency-based, implementation, review, secondary, school.