Family businesses are a cornerstone of the Portuguese economy, representing around 80% of all enterprises, generating two-thirds of GDP, and employing half of the national workforce. Despite their long-term orientation and resilience, these organisations face key challenges, such as succession, professionalisation of management, and resistance to change. In this context, psychological safety emerges as a pivotal construct in promoting work engagement and employee wellbeing. This study investigates the effect of psychological safety on work engagement, considering job satisfaction and resilience as mediating variables. It also examines the mediating role of psychological safety in the relationship between transformational leadership and work engagement. A cross-sectional survey was conducted among 800 employees from Portuguese family businesses. Participants completed a self-report questionnaire comprising validated measures: Team Psychological Safety Scale, Utrecht Work Engagement Scale (UWES-3), Short Index of Job Satisfaction, Psychological Capital Questionnaire (resilience subscale), and the Global Transformational Leadership Scale. Data collection followed ethical approval and informed consent procedures. Preliminary analyses suggest that psychological safety is positively associated with engagement, job satisfaction, and resilience. Mediation analyses are being conducted to assess the indirect effects of job satisfaction and resilience on the relationship between psychological safety and engagement. Additionally, results are expected to demonstrate that transformational leadership positively influences psychological safety, which in turn fosters work engagement. Findings are expected to offer both theoretical and practical contributions to organizational psychology by clarifying the mechanisms through which psychological safety enhances motivation and performance in family business contexts. The study highlights the relevance of promoting psychologically safe environments, supported by transformational leaders, as a pathway to sustained employee engagement and organisational adaptability.