Government 3.0, which builds on openness and transparency, sharing, increased communication and collaboration, government reorganization through integration and interoperability, and use of new technologies, is an emerging concept in eGovernance. However, few systems that qualify as Government 3.0 have been described in detail so far. And there is a lack of research on how governments can put in place such systems. This study investigates and characterizes an innovative eGovernment project, based on Open Source Software (OSS), that could be considered as an example of a Government 3.0 project. Therefore, we report from a case study of X-Road, an originally Estonian eGovernment project for creating a data sharing infrastructure, which today is also used in other countries. We present the main characteristics of X-Road from the point of view of Government 3.0, how the X-Road project is organized, compare its organization to other OSS projects, identify who contributes to the project, and point out what challenges are perceived by their stakeholders. We conclude offering some reflections on how X-Road and other Government 3.0 projects can benefit from OSS.