Grid computing systems utilize the heterogeneous networked resources, such as computation, information, database, storage, bandwidth, etc., through the Internet. The systems can operate in predefined and organized ways or form the collected resource systems through self-organizing and decentralized ways. Even with the various types of abundant resources in the Internet, the resources that can be organized and operated in the presence of multiple resource owners with the uncertainty of resource availability and quality are scarce.This volume contains refereed and invited papers presented at the 3rd International Workshop on Grid Economics and Business Models held on 16 May 2006 at the Singapore Management University, in conjunction with GridAsia 2006. It includes contributions by researchers and practitioners from multiple disciplines that discuss the economy of the systems concerned, with focus on the operational and deployment issues of Grid Economy.