An online survey covering a variety of mental health and work-related questions in the context of COVID-19 with follow up at 4, 12 and 18 months after the baseline survey. The survey will be distributed to health and social care staf at 12 NHS Trusts (as part of the NHS CHECK national cohort study). An “ethnicity module” will be added to the survey at the 6-9 month follow-up stage, incorporating questions to assess possible mechanism underpinning poorer occupational and mental health outcomes for Black, Asian and minority ethnic staff.