On 01/04/19, Moreno Andreo (moreno.andreo@xxxxxxxxxx) wrote: ... > I'm not forced to use pseudonimysation if there's the risk to get > things worse in a system. I've got to speak about these"two opposing > forces at work" to a privacy expert (maybe choosing another one, as > Peter suggested :-) ) and ask him if it could be used as a matter of > declining pseudonymisation because of "pseudonimysation puts at risk > overall performance or database integrity" How to interpret the pseudonymisation conditions is ... complicated. The UK's Information Commissioner's Office (ICO) writes that pseudoanonymisation relates to: “…the processing of personal data in such a manner that the personal data can no longer be attributed to a specific data subject without the use of additional information, provided that such additional information is kept separately and is subject to technical and organisational measures to ensure that the personal data are not attributed to an identified or identifiable natural person.” and that this "...can reduce the risks to the data subjects". The concept of application realms may be relevant to consider here. An application may be considered GDPR compliant without pseudonymisation if other measures are taken and the use case is appropriate. On the other hand, a copy of a production database in testing which has been pseudonymised may, if compromised, still leak personal data. As the ICO states: “…Personal data which have undergone pseudonymisation, which could be attributed to a natural person by the use of additional information should be considered to be information on an identifiable natural person…” https://ico.org.uk/for-organisations/guide-to-data-protection/guide-to-the-general-data-protection-regulation-gdpr/what-is-personal-data/what-is-personal-data/ If leakage occurs pseudonymisation has achieved nothing. Therefore it may be useful to determine if data in a usage realm should be either fully anonymised or not at all. In the latter case the normal GDPR controls must all pertain. Rory