– The purpose of this paper is to investigate the external and internal factors that contribute to assimilation of enterprise resource planning (ERP) system in the organization through the processes of adapting, routinizing and institutionalization of technology. , – This research follows qualitative interpretive approach. The results produced in this paper are based on thematic analysis of responses from open-ended interviews with ERP stakeholders in large size Australian organizations. The research findings have been further triangulated with surveys and content analysis. , – This research is still in progress; therefore, this paper presents the results of the field study conducted so far along with the instrument used to collect data. This instrument consists of a list of selected questions based on the thorough review of current information systems literature. However, the major finding of this study, thus far, is that the ERP implementation is a process of aligning technology with organizational, social, cultural, economic, technical, and other organizational environmental institutions. , – The major research limitation of this study is that it is still in progress, therefore, the results reported in this paper are emergent and not complete. Another limitation of this paper is that it is Australian specific; therefore, the generalizability of the results in other settings cannot be ascertained. Nevertheless, this research contributes to the ERP implementation literature by applying a stage-based model which takes into account the pre-implementation, implementation and post-implementation stages of ERP assimilation into an integrated structure. , – This research concludes that ERP assimilation is characterized and shaped by mutual interactions of various organizational, social, cultural, environmental, and other institutional factors. The research framework developed in this study may be mastered as a decision-making tool by business manager to guide the organization through various stages of ERP institutionalization. , – Institutionalization of ERP technologies is a recent phenomenon and this field is far for being matured. This research is based in Australian settings where they have been no previous study of institutionalization of technology.