The objective of the article is to go beyond the knowledge integration barriers in ERP implementations by analyzing structural, technological, intellectual and socio-emotional barriers that appear during an ERP implementation project. Using an action research methodology, the article provides some hints highlighting the knowledge integration process, and proposing an Institutional Model of ERP Knowledge Integration where ERP “best-practices” affect and are affected by institutional logics through legitimacy and isomorphism mechanisms, showing two processes of institutionalization: (1) processes that challenge knowledge integration barriers by embedding ERP “best-practices” in the expected formal functioning of the organization as well as in the routines and habits of employees; and (2) processes that operate as drivers of evolution and change by embedding the institutional logics and new requirements within ERP “best-practices”.