. In this PLOScast, Elizabeth Seiver speaks with Geoff Builder, Strategic Director at CrossRef, about link rot, unique digital identifiers and the infrastructure needed in order to support persistent links. This episode also covers: • The history of CrossRef • Why metadata is important for publishers • Organizational identifiers for institutions with ORCID and DataCite • Using DOIs for work other than journal articles such as books, software, figures and data • Benefits of DOIs for researchers