In this "information and knowledge" age, instead of traditional financial assets and even large markets, knowledge capital has been the competitive edge for major corporations. This has lead to a new concept called "knowledge management". Indeed, the identification of knowledge in business sectors as a competitive advantage and strategic resource intensifies the necessity of implementation of knowledge management (KM) in organizations. Knowledge management is the process of identifying, selecting, organizing, and transferring important information and skills, which exists as disorganized form in the organization. However, there are several stories of failed implementation of knowledge management in organizations. In order to succeed in implementing knowledge management, identification of the success factors for knowledge management is of great importance. The current research has therefore presented a conceptual model for implementing knowledge management successfully in Tehran municipality. This study has first identified effective variables on success of knowledge management; then has evaluated its significance and developed a conceptual model for the critical factors on successful knowledge management in the organization under study. According to the conceptual model offered by this research, these critical success factors are dimensions of organizational culture, strategy and leadership, organizational structure, information technology infrastructure and human resources.