Currently, client and supplier firms are struggling with how they can make their information systems (IS) outsourcing engagements more valuable. This research points to the importance of successful practice and outcome in IS outsourcing for achieving engagements of value. To enhance the understanding of IS out­sourcing over time, a process perspective is applied. Further, this research is based on the contention that IS outsourcing is more likely to be successful if challenges are managed in a proactive manner and with a relationship perspective. Thus, understanding challenges in IS outsourcing requires a symmetric view on client and supplier. The thesis is based on two studies presented as three steps of research: development, validation and reconsideration of a conceptual framework. The licentiate study centred on the step of development whereas the present doctoral study has a focus on the steps of validation and reconsideration. The purpose of this study includes investigating how the management of successful practice and outcome in IS outsourcing can be enabled. To address the purpose, the IS outsourcing process is studied in a client–supplier relationship. This includes that different actor perspectives, including strategic, operative, and systems, are considered for a better understanding of the practice of IS outsourcing, the challenges, and how different actors convey successful IS outsourcing. The thesis contributes a framework for relational-oriented management of IS outsourcing, which provides the structure for understanding what needs to be managed in terms of key conditions, when and how in connection to actors, relationships, and process. Theoretical propositions, enhancing the understanding of the complexity of IS outsourcing as well as the number of challenges involved, are also presented. In brief, these propositions relate to the circumstance that IS outsourcing requires management on different levels and with different kinds of results in mind.