Working with knowledge implies understanding the organization as a system. Effective work demands creation, sharing and distribution of information as the new material that individuals and organizations process into knowledge. Using knowledge requires individual and organizational learning and interaction. As actor in a system, human participants enable an organization to learn. Individuals share and improve, effectively recycle the existing knowledge. Knowledge management is seen as offering a substantial enhancement of the role of the information professional and an opportunity to rejuvenate the profession. Librarians and information professional have also responded to the knowledge management movement. This paper describe overview of knowledgemanagement: definition, objective, trends in knowledge management, understanding of knowledge management and changes involved in knowledge management.