CLGTM04More than 3/4 of large software projects suffer large cost and schedule overruns or fail outright. Deficits in project requirements cause more than half of these failures and overruns. This is in part because the establishing of software requirements is fraught with complexity. Finding ways to manage that complexity might be an important step in reducing the risk of software development. Group Support Systems (GSS) offer functionality that may reduce some aspects of complexity and reduce the cognitive load of addressing other aspects of complexity. In this paper we examine the sources of causes of complexity in software requirements in the context of EasyWinWin, a requirements negotiation methodology supported by GSS. Early field trials suggest that EasyWinWin is a significant step forward in managing the complexity of establishing requirements, and that further advantage could be gained by combining a GSS solution with other technologies like intelligent agents and requirements management systems.