The project group worked in English. Participants recognised the challenges of achieving a shared understanding of precise meanings, especially in the case of words that may have several usages in everyday non technical language, rather than those that are specialist technical terms unique to transfusion.

The glossary is based as far as possible on definitions used in the EU Directives or taken from standard dictionaries. Where other definitions are used, the source is identified. Some key terms and definitions are also mentioned in the text.