Many organisations get together in order to make business. They create and maintain relations and their relationships are supported by inter-organisational information systems (IOIS). When developing IOIS the participating organisations must co-ordinate their activities and decide who in which organisation are going to do what, how, when and why. They have to define their business relation. To be able to perform in a business,people need information and material (e.g. order, goods and payment). When developing IOIS one has to make sure that the information and material flows run efficiently through the whole chain of parti-ci-pa-ting organisations. The business context indicates what kind of information and material the busi-ness needs. A context in which roles, business relations,parties, business actions and business transac-tions are central. A method to support IOIS development should be based on a communicative action perspective in business modelling, design and redesign to help focu-sing on actors (sender and recipient), exchanged information and material (both contents and communicative action) and actorÕs responsibi-lity for performing expected actions. This paper is based on my experiences in using parts of the SIMM method in an inter-organisational change analysis. In the case study methods for analysing business pro-cesses where extended to an inter-organisational focus. The paper presents, discusses and argues for the needs and benefits of Interaction Analysis, a method that puts human actors (agents) and action in the foreground when studying information systems and organisations. It is a method to support inter-organisational business and IS development when focusing on communication flows, business transactions, expected business actions and responsibility of actors in internal processes and in the interaction between parties. This in order to gain knowledge and understanding about actions performed by each organisation and/or together, to develop professional relationships which may gain win-win situations based on understanding of the inter-organisational business process and each organisations contribution