Claudio Ciborra's improvisation argument provides a realistic dynamic account of how organizational practices address technology. This was developed from the study of malleable open-ended technology, but little research has occurred to investigate the theory's validity within different settings. This paper seeks to address this gap, by examining improvisation in the context of a rigid highly structured technology. It presents findings from the successful implementation of an Enterprise Resource Planning (ERP) system within a large international organization, which was subsequently defined by the ERP vendor as being an "exemplary site". Through the theoretical lens of Actor Network Theory, the paper reveals the improvisation, enactments and constant work around the plan that took place in dealing with the high contingencies of ERP implementation. The study extends the discussion on improvisation and contributes to an already illuminating argument. It invites practitioners to reflect on ERP implementation practice and review their evaluation methods.