An information system is widely recognised as a technological-political system and it can be better understood from a political perspective. This research studies how an information system is socially and politically constructed through the implementation process. It posits that the process of information system implementation can be shaped and impacted by power relations and thus that failing to understand such phenomena will contribute to system failure. The aim of this research is to broaden the understanding of an information system from a power perspective. Particular emphasis is placed on power relations in organisations and how such relations impact the process of system implementation. In order to achieve this aim, the research applies an integrated theoretical framework based on power and discourse perspectives to two qualitative case studies carried out in companies in Thailand. The case studies were undertaken based on an interpretive mode of inquiry, which provides ways of understanding how the process of implementation of information systems was shaped and impacted by human actions and political processes. lnterpretivism helped to explore the complexity of human action and meanings that system participants assigned to those actions leading to the system implementation process. The main findings suggest that information system implementation can be impacted by power relations enacted through discursive actions of textual practices 2 I constituting discourse. Besides, a grand discourse can itself be a source of power that affects the system implementation process. The findings indicate that: i) knowledge integrated in discourse plays a prominent role in power relations, ii) discursive legitimacy could enable and at the same time delimit the exercise of power, and iii) an information system may be used as an apparatus for domination as well as human emancipation. The main findings are taken as significant contributions to both theory and practice in the information systems field. 3