Implementation is one of the stages of public policy process which refers to the putting into practice of policies projects. It is a purely practical step involved in administrative, organizational, political issues and not only and, therefore, it is extremely difficult to achieve successfully. Paper aims to identify the main models of implementation (the implementation as system management, the implementation as bureaucratic process, the implementation as organizational development and the implementation as negotiation), with their pluses and minuses and to outline a design process at the administrative level.