Recent estimates suggest that up to 34% of frontline workers in healthcare (FLWs) at the forefront of the COVID-19 pandemic response are reporting elevated symptoms of psychological distress due to resource constraints, ineffective treatments, and concerns about self-contamination. However, little systematic research has been carried out to assess the mental health needs of FLWs in Europe, or the extent of psychological suffering in FLWs within different European countries of varying outbreak severity. Accordingly, this project will employ a mixed-methods approach over three work packages to develop best-practice guidelines for alleviating psychological distress in FLWs during the different phases of the pandemic. Work package 1 will identify the point and long-term prevalence of psychological distress symptoms in a sample of Irish and Italian FLWs, and the predictors of these symptoms. Work package 2 will perform a qualitative needs assessment on a sample of Irish and Italian FLWs to identify sources of stress and resilience, barriers to psychological care, and optimal strategies for alleviating psychological distress in relation to the COVID-19 pandemic. Work package 3 will synthesise the findings from the preceding work packages to draft best practice guidelines, which will be co-created by a multidisciplinary panel of experts using the Delphi method. The guidelines will provide clinicians with a framework for alleviating psychological distress in FLWs, with particular relevance to the COVID-19 pandemic, but may also have relevance for future pandemics and other public health emergencies.