In the everyday business world, the sourcing process of multiple goods and services usually involves complex negotiations (via telephone, fax, etc) that include discussion of product and service features. Nowadays, this is a high-cost process due to the scarce use of tools that streamline this negotiation process and assist purchasing managers’ decision-making. With the advent of Internet-based technologies, it has become feasible the idea of tools enabling lowcost, assisted, fluid, on-line dialogs between buyer enterprises and their providers wherever they are located. Consequently, several commercial systems to support on-line negotiations (esourcing tools) have been released. It is our view that there is still a need for these systems to incorporate effective decision support. This article presents the foundations of Quotes, a commercial sourcing application developed by iSOCO that, in addition to cover the whole sequence of sourcing tasks, incorporates decision support facilitie...