The impact of Lean methodology on supply chain

This study explores the impact of Lean methodology on supply chain operations, with a focus on two key tools: Value Stream Mapping (VSM) and Just-in-Time (JIT). Despite the widespread recognition of Lean principles, such as waste elimination and continuous improvement, many organizations struggle to extend these practices effectively across their supply chains. To address this gap, the research adopts a qualitative exploratory methodology through a single case study carried out at Transfor, a Portuguese industrial firm operating in carpentry, metal work and modular construction. The study is conducted with semi-structured interviews with key company personnel, enabling a practical analysis of Lean tools implementation across the supply chain. The findings reveal that both Lean tools provide distinct but complementary contributions, where VSM offers strategic mapping and waste identification, while JIT enhances synchronization and reduces inventory costs. Since Transfor Industry is composed by three sub-industries, the effectiveness of each one varies by sub-industry, since, in turn, the suppliers of each are slightly different. The study concludes also that combining both tools can significantly improve supply chain performance, provided they are tailored to the operational context of each unit.