Nowadays, all the enterprises in the fashion industry face the problem of variability of supply and demand. Working in fashion implies facing rapid changes, and the success or failure of a company is often determined by the company's ability to adapt and respond quickly to these changes. In addition to having to deal with large quantities of information, the companies must ensure the availability of all their products, in all the stores worldwide, while optimizing inventory levels. This research will focus on Christian Dior Couture and more specifically on the Eyewear. The immediate objective of this research project is to optimize the inventory while maintaining the sales. The information on stock out rates crossed with the sales quantity, the stock and the coverage enables supply chain's managers to make decisions at a store level and at a reference level to reduce the stock at its optimal value without compromising the sales' level. In the future, further studies could be made to try and optimise the reordered quantities in addition to optimizing the current stores' stock.