This case study analyses a multiyear ERP (SAP R/3) implementation project in a global company from perspectives of conflicts and problems the project faced. The paper reports on the core of the implementation activities from the start of the project in late 1995 until mid 2000, when most of the originally estimated implementation efforts were finished. The study reveals what pitfalls an inappropriate understanding of the magnitude of changes required for implementation involves and what unidentified consequences can result from this. The main reasons for problems encountered are discussed and analysed. The main lesson of the study is that the fundamental challenge of ERP implementations is not technology but organisational and human changes, which, if not properly understood and addressed, can lead to unidentified consequences causing implementation failures.