A de-identified 'live' data resource sourced from the electronic health records of SLaM - a mental health Trust providing services to four south London boroughs CRIS provides researcher access to a live de-identified copy of SLaM's electronic health record, currently representing over 400,000 mental health service users. Structured and text fields are represented, the latter enhanced through a range of natural language processing algorithms. CRIS has also been linked to a range of external data resources, listed on http://www.maudsleybrc.nihr.ac.uk/facilities/clinical-record-interactive-search-cris. CRIS data are held within SLaM's firewall and are used within a patient-led governance framework with Caldicott and Research Ethics approval.