Problems associated with ERP implementations are most prevalent during the post-implementation phase because this is when the mistakes of the prior phases surface and become real. The cost overruns and adverse business impacts in an organization during this phase can threaten the survival of the organization and impact sales revenue. For this reason, research that increases our understanding of this phase in order to minimize the negative impacts and failure during this period is critical. This study utilizes variance research to explain similarities and differences in post-implementation outcomes across organizations that have implemented or upgraded their ERP systems. This approach does this by linking post-implementation outcomes to varying levels of IT governance. IT governance is examined by studying the ownership, accountability, and decision making structures in each organization. In-depth interviews were conducted with twenty-two participants in four organizations that implemented ERP systems. Analysis of the data collected across all cases resulted in initial propositions that can be investigated further.