In this paper we propose a situated decision support system for efficient negotiating of service level agreements (SLAs) in Grids. Situated deci- sion support systems effectively combine human judgment with autonomous decision making and action by agents. The intuition of using this ap- proach for SLA negotiations lies in the monitor- ing and controlling of the fleet of local agents negotiating single services from multiple service providers by the use of a "manager" agent and human decision maker. We show through nu- merical experiments that the approach performs well under a set of simplifying assumptions.