Lean practice implementation in French healthcare: a longitudinal case study.

This paper examines how Lean was introduced, implemented and sustained in a French public hospital and identifies the organisational drivers that supported this journey. A qualitative, longitudinal single-case study was conducted over five years at "Greta Hospital". Data from interviews, non-participant observations and internal documents were coded thematically and interpreted in light of Lean healthcare literature to derive five overarching drivers. Lean projects in the operating room, the sterilisation service department, the discharge "Sortology" unit, and the biology and genetic laboratories delivered measurable gains in operating theatre performance, supply reliability, and the management of complex discharges. Over time, these initiatives evolved into a more integrated Lean system. The analysis highlights five interdependent drivers of sustainable deployment: visible direction commitment, patient focus, cross-functional team and portfolio design, step-by-step conversions and remaining close to the field. The findings stem from a single French public hospital and should be generalised cautiously, but they offer analytically generalisable insights into how Lean capabilities accumulate over time and how these drivers interact in complex healthcare settings. The paper provides guidance for hospital leaders and policymakers on structuring Lean deployment, including project selection, team composition, pacing, and leadership's connection with frontline work. The study contributes rare longitudinal, organisation-wide evidence on Lean healthcare in the French context and consolidates dispersed success factors into a process-based framework of five reinforcing drivers.