Aims : To summarize the clinical evidence for a pathogenic role of small airway cells in COVID-19 and fibrosing lung diseases; to explore the novel concept that small airways are central to the processes involved in regenerating and repairing a fibrosing lung. New developments regarding innovative in vitro models will allow us to exploit the regenerative and therapeutic potential of modulating small airway cells in lung fibrosis. AIMS: To highlight the contribution of small airway cells in COVID-19 and lung fibrosis from a clinical perspective; to understand the key role of small airway cells in lung regeneration and fibrosis; to demonstrate the regenerative potential of small airway cells and their likelihood as new therapeutic targets for pulmonary fibrosis; to explore novel models to study small airway cells and their regenerative capacities in pulmonary fibrosing diseases.