Over the past decade there has been an increasing awareness of the potential for data science to make important advances in brain and mental health research. This focus has coincided with the use of electronic health records in the clinic, the advent of electronic remote data capture through smart devices, publicly available de-identified large data sets, and the emergence of research consortia collaborating on the analysis of complex data sets. Interest in data science in mental health research has been further heightened by the widely acknowledged need for improved diagnostic precision and individualised risk prediction, long-term monitoring, and treatment. Using big data approaches to tackle complex mental health problems is now felt to be a key research priority moving forward. Therefore, Evidence Based Mental Health has dedicated the current Special Issue to address the question ‘How can we use data analysis to tackle mental health issues like depression, dementia diagnosis,…