Curricular reform is often proposed as the means to improve medical education and training. However, reform itself may not lead to noticeable change, possibly because the influence of organisational culture on change is given insufficient attention. We used a national reform of early-years surgical training as a natural opportunity to examine the interplay between organisational culture and change in surgical education. Our specific research question was: in what ways did organisational culture influence the implementation of Improving Surgical Training (IST)? This is a qualitative study underpinned by social constructivism. Interviews were conducted with core surgical trainees (n = 46) and their supervising consultants (n = 25) across Scotland in 2020-2021. Data coding and analysis were initially inductive. The themes indicated the importance of many cultural factors as barriers or enablers to IST implementation. We therefore carried out a deductive, secondary data analysis using Johnson's (1988) cultural web model to identify and examine the different elements of organisational culture and their impact on IST. The cultural web enabled a detailed understanding of how organisational culture influenced IST implementation as per Johnson's six elements-Rituals and Routines (e.g. departmental rotas), Stories (e.g. historical training norms and culture), Symbols (e.g. feedback mechanisms, visibility and value placed on education), Power Structures (e.g. who has the power in local contexts), Organisational Structures (e.g. relationships and accountability) and the Control System (e.g. consultant job plans and service targets)-and how these interact. However, it did not shed light on the influence of exogenous events on change. Our data reveal cultural reasons why this curricular reform met with varying degrees of success across different hospital sites, reinforcing that curricular reform is not simply about putting recommendations into practice. Many different aspects of context must be considered when planning and evaluating change in medical education and training.