From 1953‒1964 Noel Muylle studied classics, commerce, and economics, followed by a post-graduate course in conference interpreting and translation at the Sorbonne. After a career of 40 years with the European Commission, he retired on August 1, 2004, as Honorary Director General of the European Commission.

As a manager, Noel held responsibilities for training, selection, and further training of staff involvement, i.e. quality control and staff career development; he was in charge of relations with the media as well as ensuring working relations with the other European Institutions and International Organizations (IAMLADP) with which DG Interpretation works closely. He regularly chaired selection panels and open competition juries, and participated closely in screening and audit procedures within the DG. He advised on the building and equipment of conference centres of the Institutions, and introduced the first IT system (SAFIR) in the Service. He set up the European Master in Conference Interpreting (EMCI) and advised authorities and universities in candidate countries, as well as in China, Vietnam, and Russia on the same.

Noel is a member of the ELC (European Language Council), IAPCO (the International Association of Professional Congress Organizers), CIUTI (Inter-University Conference for Translation and Interpreting), LISA (the Localization Industry Standards Association), IAMLADP (International Annual Meeting on Language Arrangements, Documentation and Publications), the Institute of Linguists, the High-Level Group on Multilingualism of EC, and DYLAN (Dynamics in Languages, a R&D program financed by EU).

He is an active member of the Belgian Branch of the European Movement (MEB) for which he held the post of Secretary General for many years.