Rodrigo Costas is a senior researcher at the Centre for Science and Technology Studies (CWTS) at Leiden University (the Netherlands). Rodrigo is also an Extraordinary Associate Professor at the Centre for Research on Evaluation, Science and Technology (CREST) of Stellenbosch University (South Africa). He holds a PhD in Library and Information Science from the CSIC in Spain. His areas of expertise include the fields of information science, scientometrics, and social media metrics. At CWTS he leads the research line in ‘altmetrics’, focused on developing new theoretical and analytical approaches to study the interactions between social media and science. Some of his other topics of research include the development of advanced scientometric studies of individual scholars and the study of funding acknowledgments as a new source of scientometric data. In addition to his research activities, Rodrigo is also involved in various European and contract research projects.