Value webs are cooperating, networked enterprises and end-consumers that create, distribute, and consume things of economic value. The task of creating, designing, and analyzing such webs is a prototypical example of a multi-disciplinary task. Business-oriented stakeholders are involved because the way an enterprise creates economic value is discussed. But also representatives responsible for business processes (many innovative value webs require changes in processes) and inter-organizational information systems (enabling value webs from a technical point of view) play a key role, as well as end-consumers. To facilitate exploration and analysis of such value webs, we propose an approach called e3value that utilizes terminology from business sciences, marketing, and axiology but is founded on methodology seen in requirements engineering such as semi-formal, lightweight graphical conceptual modeling, multiple viewpoints, and scenario techniques. We have developed and tested this methodology in a series of e-business consultancy projects. In this chapter we will present lessons learned in developing value webs, which stem from our consultancy experience. Then we present the e3value methodology, with a focus on modeling and understanding what parties offer each other of economic value. Analysing value webs from such an economic value perspective is the main contribution of our approach; business science approaches contain the right terminology but are far too sloppy to be usable in practice, whereas requirements engineering and conceptual modeling approaches are sufficiently rigorous but do not provide adequate terminology. For educational purposes, we illustrate the methodology with an easy-to-understand, inline example. Finally we discuss related approaches and conclusions.