Abstract: Collaboration and the sharing of knowledge is at the heart of Open Science. However, we need to know that the knowledge we find and share is really what it purports to be; and we need to know that the authors we hope to collaborate with are really the people they claim to be. In this paper, the author argues that a prerequisite for Open Science is trust and that persistent identifiers help to build that trust. The persistent identifier systems must themselves be trustworthy and they must be able to connect the user or their machine to the information they need now and into the future. Infrastructure is rather like plumbing: it goes unnoticed and unappreciated until it fails. This paper puts infrastructure for persistent identifiers in the spotlight as a core component of Open Science.