The first Ruisdael Science Day (formerly called the CESAR Science Day) was held on the 31st of May 2018. This yearly event aims at bringing together scientists who work within the framework of the Ruisdael project or related science projects. In this way, cooperation between the various disciplines that are represented within Ruisdael is stimulated. Instrumentalists, data analysts and modellers were encouraged to present their work. At this site you can find the programme of the Ruisdael Science Day 2018 and links to presentations and posters. More than 25 scientists, PhD students and post-docs of the affiliated institutes attended the first Ruisdael Science day.