To date, studies on reflection seem to lack concern for in-service teacher development. This article proposes a new EFL reflective practitioner development model (RPDM) for an in-service program that is not only based on the principles of reflection, but that also measures teachers' reflective and self-efficacy development. Focusing on the improving practitioners' reflective abilities, the model emphasizes building self-efficacy and delineates the program's procedure to achieve these goals. The model was tested by collecting quantitative and qualitative data. The findings suggest that the model would be effective for educators to use as it facilitates and improves teachers' abilities to reflect and their overall self-efficacy.