This thesis is based on my internship experience at Amazon Luxembourg, in which I held the role of Project Manager Intern in a team specialised in optimising processes within European Sort Centres, which are key warehousing facilities used by Amazon to ensure efficient delivery to end customers. The main objective of this research is to emphasise the importance of the continuous improvement philosophy in today's business environment. It highlights how crucial it is for companies to adopt a continuous improvement approach in order to meet the changing needs of consumers and maintain competitiveness in the marketplace. The paper presents two case studies that concretely illustrate how a web application developed for labour planning process within Sort Centres can be optimised.