The Impact of a Training Program on EFL Post-basic Education Female Teachers' Knowledge and Practice of Critical Thinking Skills in Oman This study investigated the effect of a proposed training program on the development of post-basic education teachers' critical thinking skills in terms of knowledge and practice. It posited two main research questions: 1. What is the impact of the training program on post-basic education teachers' knowledge of critical thinking skills? 2. What is the impact of the training program on post-basic education teachers' classroom practice of teaching critical thinking skills? The sample included five female EFL post-basic education teachers in one of the female government schools in Saham in the North Batinah Governorate in Oman. The researcher used a quasi-experimental research design, pre-test and post-test one group design. The quantitative data were collected through a questionnaire and a classroom observation checklist. The questionnaire was used to compare the teachers' knowledge of critical thinking skills before and after receiving the training. It was also used to assess the training program's participants' knowledge of critical thinking skills. The classroom observation checklist was used to measure the frequency of use of the strategies of critical thinking in the classroom before and after the teachers had followed the training program. The results of this research study revealed that the training program positively affected the teachers' knowledge and practice of critical thinking skills. In light of this study's findings, the researcher outlined a number of recommendations for further research and practice.