This chapter aims at taking stock of Blockchain from a public administration perspective. Blockchain is a technology allowing the tamper-resistant recording of transactions and the resilient distribution of data at a global level without the need for trust in any central actor. This chapter presents the technology to a non- specialist audience. It emphasises that the competitive advantage of this technology over centralised databases is decentralisation and security; centralised databases will always remain more efficient and easier to update. Its main application to date has been in the private financial sector; building further on the Bitcoin network and later evolutions, a cryptocurrency industry has emerged. This chapter presents this emerging sector to a public administration audience with a view on establishing trust through upcoming regulatory initiatives. Its key properties (capacity to achieve coordination with no need for a central actor to be trusted, and public availability of coordination outputs) make it especially relevant in the public sector, with numerous potential applications in the field of ownership documents, financial management, and public participation (Beryhill et al., 2018). A case study related to diplomas in Europe and lessons from a first generation of public sector Blockchain projects are presented. It is suggested that the technology can indeed allow running some government workflows. Reasonable expectations should be adopted, beyond the hype surrounding the technology.