Investigating on lean supply chain planning

Both practitioners and scientist recognise importance of supply chain planning (SCP) for improving supply chain (SC) effectiveness and efficiency. SCP is that branch of Supply Chain management that coordinates and aligns operations of different actors in a supply chain. Although many SCP models have been developed in past decades, the debate on the best SCP policy is still an open issue and there is an increasing interest in finding new approaches and methodologies. Lean management proposed one: despite it is becoming more and more popular among operations managers, research providing sound theoretical foundations of Lean in SCP (LSCP) is still limited. Lean management developed in manufacturing production system, it became famous for its struggle against wastes and its application in SCP fields looks promising. Authors, which studied LSCP, classified concepts/practices/tools that belong to Lean SCP sphere but there is not a deep study that reveals quantitatively and analytically the impacts of their implementation. The presented work focuses on the evaluation of adoption of Lean practices in SCP, following two main research objectives: • The first, understanding performances of Lean as supply chain planning model comparing LSCP with other SCP models; The second, understanding more in detail which are LSCP practices effects along the SC, in order to reach the best possible results from LSCP adoption. The first objective aimed at proving that LSCP is a valuable option for SC managers to gain competitive advantages. A simulation study that compares LSCP with a Visibility SCP model has been set, measuring inventory and transportation SC performances. Results gave contrasting indications about the profitability of adopting LSCP, without clarifying which model performs better. Then, a new framework for supporting evaluation of different SCP models adoption has been provided. The second objective aimed at deeply understanding LSCP practices impact on SC performance, detailing three specific aspects: (i) how improvements of LSCP adoption are distributed along the chain, (ii) how much the impact of a practice is influenced by the level of adoption of other LSCP practices and (iii) how much the impact of LSCP adoption by a SC member is influenced by the participation of the other SC partners. A simulation study in a three-echelon and multi-product SC has been carried out. The results demonstrated that: (i) a great part of improvements stays along the SC instead of where LSCP practice is applied; (ii) there are synergies among LSCP practices, actual improvement of adopting all practices concurrently is greater than the sum of single practice adoptions; (iii) the improvements of adopting LSCP increases more than linearly while the number of SC partners that participate increases. The work demonstrates that LSCP is a valuable option for gaining competitive advantage and gives a framework for supporting managers on evaluating it. In addition, a deep study focused on LSCP practices highlighted relevant aspects of LSCP adoption which are not banal to foresee, but that have a significant role on determining if LSCP journey will be successful or not.