Nees Jan van Eck is a researcher at the Centre for Science and Technology Studies (CWTS) of Leiden University in the Netherlands. His research focuses on the development of visualization tools and algorithms, mainly for analyzing the structure and development of science. Nees Jan has published numerous scientific articles on this topic. The VOSviewer tool developed by Nees Jan (together with Ludo Waltman) is widely used by researchers in the field of bibliometrics and scientometrics. In 2010, Nees Jan received his PhD from Erasmus University Rotterdam. Many of the techniques used in the VOSviewer tool were originally introduced in his PhD thesis. In addition to his visualization research, Nees Jan also manages the IT department of CWTS.