Focusing on the flexibility during the recruitment and selection processes has been a trend in public human resources management. Upon the departments and agencies were empowered to select their own employees, the interview method will be applied more often. Therefore, it is necessary to pay more attention to improve the validity and reliability of the interview design and application for both theoretical and practical concerns. This article explored the design method and process of a competency-based situational interview and surveyed specified-duty officers in the R.O.C. Military. The results indicate that such design provides with reliability and content validity. Keywords: Flexible Recruitment and Selection of Government Personnel System, Competency-based interview, Situational interview, Assigned Specialty Officers and Sergeants for Armed Forces