Purpose– The purpose of this article is to propose a theoretical model explaining information technology outsourcing performance in the public sector as well as a set of empirically testable propositions to improve the understanding of key determinants of success.Design/methodology/approach– Based on Fountain ' s technology enactment framework, the authors integrated inter-organizational factors, such as trust, knowledge sharing, and quality of outsourcing interfaces, in the model and added organizational culture alignment between service providers and public administration to enhance Fountain ' s original framework.Findings– The authors proposed 17 empirically testable propositions to establish the relationships between key variables in IT outsourcing projects in the public sector.Research limitations/implications– The proposed model provides guidance for future research aimed at advancing knowledge of IT outsourcing.Originality/value– The contribution lies in the development of specific variables, such as trust, knowledge, and organizational culture, which are related to building an outsourcing relationship and are used as determinants of the quality of organizational interfaces between public bureaucracies and IT outsourcing providers.