Rising external competition and cost-pressures compel internal service providers to re-define their customer- service approach. Providing value propositions to the intra-firm end-users instead of provisioning technical resources becomes a necessity to facilitate transparency in costs and customer satisfaction. With that, the complexity of IT projects, particularly international ones, rises and changes in regards to impacts of inter-social and human factors. This paper uses a cross-case study method based on five cases to identify critical success factors for achieving IT-project success and the provision of the needed value propositions. Our analysis found that seven major factors are essential for the project success when coupled with a clear customer-oriented value proposition: one of the most important ones is to understand the customer’s business and with it to identify the end-user’s requirements. Furthermore, a close project collaboration, process alignment and trustful, clear communication as well the right choice of personnel emerge as important factors. Inter-social factors like support of the top-management and the early identification of stakeholders are equally crucial. Top management support acts as enabler for all these success factors. With the insight into requirements and impacts of each success factor, this cross-case study poses as operational guidance to achieve value propositions in IT-projects.