AbstractVaccination uptake is essential to controlling the ongoing COVID-19 pandemic. Healthcare workers (HCWs) play a critical role in receiving, recommending and delivering COVID-19 vaccination. Understanding the specific influences on each behaviour enables the development of targeted and tailored interventions to improve vaccination uptake. This paper presents a qualitative synthesis of HCWs’ individual and context barriers and drivers to these three vaccination behaviours across 10 countries in Europe and Central Asia. Qualitative data from interviews and focus group discussions with 378 HCWs between December 2020 and March 2022 were synthesised and organised by four COM (capability, physical and social opportunity, motivation) factors. Differences by stage of COVID-19 vaccine roll-out (in preparation, early and late delivery) were explored. Receiving vaccination related to all four factors. Recommending vaccination mostly related to capability and motivation. HCWs were generally well-informed by official sources and viewed vaccination as the way to end the pandemic, acknowledging their important role in this. Colleagues, family and friends were positive influences on personal vaccination decisions. However, knowledge gaps were evident, particularly amongst nurses who relied on (social) media. Concerns about safety and effectiveness, often connected to knowledge gaps, were heightened by the accelerated timeline for COVID-19 vaccine development and approval. This impeded some HCWs’ motivation to receive and recommend vaccination even in the later roll-out countries. Delivering vaccination was facilitated by support from public health organisations, teamwork and service re-organisation, more evident amongst later roll-out countries. Ongoing high workloads, stress and burnout hindered delivery. Complex and inter-related factors affecting HCWs’ vaccination behaviours were identified. These insights should inform the design of multifaceted interventions (e.g., communication skills training, management support for HCWs’ mental health, and engaging them in decision-making for service redesign); not only for COVID-19 vaccination as it is integrated into routine services but for routine immunization as a whole.