ABSTRACT A group support system (GSS) is a computer-based system that enables people in different places to discuss and make decisions on connected computers. Expanding GSS capabilities from knowledge management perspective is believed to significantly improve performance and satisfaction of group meetings. This study develops organizational knowledge management process, proposed by Alavi and Leidner (2001), to expand capabilities of a GSS. Additionally, a prototype system has been implemented. Finally, an experiment is conducted to evaluate system and demonstrate its applicability and usability. Experimental results indicate that users perceive a web-based GSS with knowledge management capabilities to be more helpful and more satisfying than a conventional GSS. They also perceived that using a web-based GSS with knowledge management capabilities can improve decision quality. INTRODUCTION Accompanied by organizational expansion and globalization, organizational decisions making are become more multi-faceted considerations for conforming to stakeholder, legislation, environment and macro economic situation. Organizational decisions are much more complex and interconnected now than in past (Courtney, 2001). Organizations now encounter with more complicated and chaotic environments than before, and thus require unequivocal decisions for rapidly to responding to critical situations. Banker and Kauffman (2004) concluded that decision makers need to discriminate between imperfect and perfect information. Decisions might be made not only by single person, but also by groups of specialists in related spheres. Communication technology can be employed to collect experts and veterans experiences in group meeting, and meet requirements of ameliorate group decision efficiency of IT researchers. Liou and Nunamaker (1999) conclude that Group Support Systems (GSS) environment can electronically facilitates seizure of knowledge. Nevertheless, until now, there are only a few GSS studies have contributed significantly to make true design-science research. Consequently, this investigation, proposes a prototype of web-based GSS with group memory and knowledge context in order to enhance efficiency of access to knowledge in GSS. A critical component of GSS-based concept-generation process is group memory, which is a granary of ideas formed by users of GSS (Satzinger, et al., 1999). Group meetings play a significant role in daily operation of most businesses. Neustadt and May (1986) observed that the future has no place to come from but past. Decision makers must understand how past affects their present decisions. In troublesome circumstance, it is controversially that any good decision could be made in a single meeting with few persons (Huber, 1990). Hence, GSS combined with collective memory is likely to provide additional information processing support (Paul et al., 2004). Williams, et al. (1988) asserted that GSS provides academics with an extraordinary opportunity to tell comprehensive details of group member interactions. Satzinger, et al., (1999) stated that group memory provides stimuli, in form of ideas, to individuals using software. Liou and Nunamaker (1990) concluded that a group meeting supported by GSS can facilitate electronic acquisition of knowledge, and distill individual experts' knowledge in a parallel fashion. Paul, et al. (2004) argued that information and knowledge are not easily accessible in large organizations and that use of group memory is expected to provide information processing support. Therefore, a shared repository that preserves prior experience of group members for group meetings needs to be developed. Orlikowski (1992) noted that group members' mental models and organization skeletons and conventions eventually affect how GSS is implemented and applied in organization. …