Paul Vitányi has been appointed 'Ridder in de Orde van de Nederlandse Leeuw'. He received this royal honour from the Amsterdam alderman Ms. Hennah Buyne during the CWI Lectures in Mathematics and Computer Science on 7 September. Keynote speakers Hendrik Lenstra (Leiden University), Andrew Yao (Beijing University) and Leonid Levin (Boston University) paid a tribute to him. Vitányi (CWI and UvA) received the honour for his excellent scholarship in the field of theoretical computer science. The book that he wrote with Ming Li on Kolmogorov complexity has become an international standard work.