This document specifies: — the general principles governing the biological evaluation of medical devices within a risk management process; — the general categorization of medical devices based on the nature and duration of their contact with the body; — the evaluation of existing relevant data from all sources; — the identification of gaps in the available data set on the basis of a risk analysis; — the identification of additional data sets necessary to analyse the biological safety of the medical device; — the assessment of the biological safety of the medical device.