The Diploma Supplement is a personal data document, produced by higher education institutions according to standards agreed by the Commission, the Council of Europe and the United Nations Educational, Scientific and Cultural Organization (UNESCO). It is also part of the Europass framework transparency tools. 

The Diploma Supplement is designed as an aid to support the recognition of academic qualifications. The Diploma Supplement is an important tool of the European Higher Education Area for graduates to ensure that their degrees are recognised by higher education institutions, public authorities and employers in their home countries and abroad. It does, however, not represent a Curriculum Vitae or a substitute for the original qualification.

The Diploma Supplement contains eight sections providing information regarding: 

• the holder of the qualification
• the qualification type and its originating institution
• the qualification level
• the content of the course and results gained
• function of the qualification
• certification of the supplement
• details of the national higher education system concerned
• other relevant details

Graduates of the School of Chemical and Environmental Engineering have the right to receive the Diploma Supplement automatically, free of charge and in Greek and in English.