The starting point of this chapter is the belief that it is neither the quality of the technology, nor that of the individual users, but the interactions amongst people in groups of users concerning a new system that determines the success or failure of IT implementation. Aiming at conceptualisation of the role of group learning in IT implementation, we first develop a theoretical framework based on the experiential learning cycle that includes five processes: collective acting, group reflecting, knowledge disseminating, sharing understanding, and mutual adjustment. Second, we illustrate the roles of learning processes in three case studies. Analysis of the interviews with 98 users of information technologies has revealed a unique function of group learning in the IT implementation. It is shown that group learning emerges immediately after a new IT is introduced to the targeted users; it may take different directions (for or against adoption of the technology); it itself can develop during the IT implementation and either progress or take a turn for the worse. The chapter elaborates on three organisational conditions important for directing the constructive group learning: managerial support issues, structural and nonstructural group characteristics, and technological features that turn group learning in a positive direction.