This paper presents a model of the Enterprise Resource Planning (ERP) software acquisition process that reflects the findings from the four cases examined in this study. This ERP acquisition process model includes six distinctive, yet interrelated, processes (planning, information search, selection, evaluation, choice, and negotiations). This paper depicts the principal processes and many of the constituent activities, issues, dynamics, and complexities that pertain to the acquisition of ERP software. The results from this study contribute to the identification of processes that are part of this type of acquisition. Further, this model also suggests complexities that are worthy of further investigation, in and of themselves, if for no other reason than that they could prove the limit of generalizability of the model.