The business models in the business-to-business (B2B) e-commerce and their effectiveness have been a major topic of research in the recent years. Due to the variety of existing models, it seems difficult to find a widely accepted categorization that can be analysed and assessed. An in-depth study that provides a process-based approach to B2B e-commerce is presented and illustrated with examples from industry. A comparative examination of both the buy and the sell side based on a process-related approach provides extensive insights for further comparative research and evaluation of products/services and models. Selling services and e-procurement using Web-electronic data interchange (EDI) as sub-models are clarified using real-world examples. Problems and trends in the B2B area form the conclusion of the examination with suggestions for further research.