The rapid worldwide growth of e-commerce and the resulting great interest on the digital business, caused a proliferation of contributes by academics and practitioners, that identified by different points of view, the fundamental concepts, codes and functions of e-business models. The quantity and the variety of approaches adopted made the concept of e-business model fuzzy and vague, with little consensus about its ontology and definition. The relevance of the topic asserts a claim for the classification of contributions as a first step to a general definition of the concept of e-business model. This paper provides an integrated literature review of contemporary academic writings to ascertain and classify the various approaches to the study of e-business models. The literature examined is classified in a content based taxonomy which highlights the relevant characteristics of e-business model, emerging from the analysis of literature. The framework proposed points out some significant implications that are a first step for further research leading to a research agenda for further investigation on this topic.