Companies face constant change in today's dynamic business landscape, navigating shifting customer demands, globalization, and economic fluctuations. To thrive, businesses must optimize costs and meet customer needs, making supply chain management necessary. At its core lies demand management, a strategic and operational process that aligns customer needs with the capabilities of the supply chain. The ever-changing demand sets challenges for the integration between supply and demand that need to be studied. While other studies may focus on individual activities, this study treats demand management as a holistic process. Through a case study in ABB Robotics focusing on the spare parts industry, renowned for its stringent service level requirements and extensive availability. This thesis investigates demand management practices, emphasizing integration between demand and supply units, uncovering challenges across the supply chain, and exploring improvement opportunities. The study employs a single case study design with an exploratory abductive approach, using a qualitative method and interviews to gather empirical data that is later analyzed against theoretical frameworks based on prior research. Despite solid inventory planning and collaboration levels, the study identifies several challenges the company faces in meeting demand effectively, including inadequate coordination and failure to incorporate supply capabilities, divergent goals, departmental silos, lack of alignment, and systematic process deficiencies hindering informed decision-making alignment. Also, unclear allocation strategies in supply limitations and customer prioritization are present. Figure 8 in this study advocates integrating demand and supply teams equally, which is crucial for optimized cost and value. The study suggests adopting Sales and Operations Planning (S&OP) to involve stakeholders systematically. Necessary actions include understanding roles and responsibilities, setting clear goals, sharing knowledge, enhancing customer and marketing segmentation, and increasing data transparency. In conclusion, successful demand management necessitates viewing it as an integrated process involving all teams focused on reducing variables through continuous information flow.