ICES is a receiver of Marine Data from national programmes and other marine institutes, therefore ICES is not the primary collection point of marine evidence that it holds and disseminates to the users of the data.

Data are quality assured using internal and external programmes. For example, the national laboratories that take part in monitoring programmes related to contaminants and biological effects that submit information to ICES, subscribe to the Quality Assurance of Information for Marine Environmental Monitoring in Europe (QUASIMEME) or the Biological Effects Quality Assurance in Monitoring Programmes (BEQUALM) inter-laboratory proficiency-testing schemes and perform internal quality assurance. ICES operates through a network of scientific expert and advisory groups. These groups, and the processes they feed into, act as a quality check on the marine evidence, both in terms of how the evidence was gathered and how the evidence has been subsequently treated. The groups, in cooperation with regional programmes under the Regional Sea Conventions, set standards and guidelines for the collection, transmission and analysis of these data.