The Initiative for Open Citations (I4OC), launched earlier this year, aims to promote the availability of open citation data. Thanks to this initiative, a large number of scientific publishers now make the reference lists of publications in their journals freely available through Crossref. CWTS believes that citation data, and publication-related data more generally, should become freely available as much as possible. We are therefore happy to express our support for I4OC. Freely available citation data will play an important role in stimulating high-quality scientometric research and in improving the quality and transparency of scientometric analyses used to support research evaluation and research management. More information about I4OC is available here.