Most empirical research on users' resistance toward Information Technology (IT) has been conducted after implementation of IT in organisations. Little research has been done on the way individual and group resistance emerges and evolves during prior stages of projects. This focus on pre-implementation phases is important since Information Systems (IS) managers need to anticipate potential conflicts and users' resistance that can involve project failure. While IS literature has separately developed theories on resistance and conflicts, we conceptualise a whole theoretic-system we call `IT Conflict-Resistance Theory' (IT-CRT). This theory is used as driver for a 2-year action research project conducted at Netia Corporation (a worldwide leader in video and audio broadcasting) during preliminary phases of its Enterprise Resource Planning (ERP) implementation project. According to our findings, while conflicts toward IT implementation are often considered to have negative ef...