Most evaluations of web-based information systems are done with respect to their effectiveness in supporting users in finding and exploring the information they need. We believe (1) that we need to move beyond task effectiveness and look at the whole-ofsystem effectiveness, and (2) that we must balance benefits with costs. We propose a method that provides guidance in whole-ofsystem evaluations, explicitly considering all participants and both sides of the “bang for buck” equation. Categories and Subject Descriptors