Although several knowledge creation and sharing systems available to date have been successful at motivating their members to contribute in content creation and sharing, they still lack formal model to systematically support community deliberation, resolve conflicts, and ensure the quality of knowledge as well as to semantically trace, search and retrieve desired knowledge. This paper aims to fill this need by analyzing the system’s key requirements and properties, and then develops Semantic Argumentation based Model (SAM), which can fulfill the identified requirements and serve as a solid foundation for such a system. SAM harnesses collective intelligence by encouraging multiple members to collaboratively express ideas or solutions regarding a complex issue, and to submit arguments which support or oppose other members’ ideas. In principle, an idea accepted or supported by most members is considered as a potential solution to solve the issue. Hence, to allow sophisticated argumentation analysis and to automatically drive the community towards a consensus, SAM Schema is constructed for formally and semantically capturing and describing the community deliberation. In addition, SAM employs ontology-based and semantic lexical-based reasoning mechanisms to enhance semantic searching and browsing as well as to facilitate users editing.