COVID-19 had a huge impact on healthcare systems globally. Institutions, care teams and individuals made considerable efforts to adapt their practices. The present longitudinal, mixed-methods study examined a large sample of healthcare institution employees in Switzerland. Organisational resilience processes were assessed by identifying problematic real-world situations and evaluating how they were managed during three phases of the pandemic's first year. Results highlighted differences between resilience processes across the different types of problematic situations encountered by healthcare workers. Four configurations of organisational resilience were identified depending on teams' performance and ability to adapt over time: "learning from mistakes", "effective development", "new standards" and "hindered resilience". Resilience trajectories differed depending on professional categories, hierarchical status and the problematic situation's perceived severity. Factors promoting or impairing organisational resilience are discussed. Findings highlighted the importance of individuals', teams' and institutions'meso- and micro-level adaptations and macro-level actors' structural actions.