He was president of the Joint Supervisory Authority set up in pursuance of the Schengen Agreement in 2002–2003, after being its vice-president in 2000–2001. In 2011, he was elected chair of the CIS-Customs Supervision Coordination Group. In 2014, he succeeded Peter Hustinx in the role of European Data Protection Supervisor, after serving as Assistant Supervisor for one mandate from 2009 to 2014.