This thesis examines IT Service Management (ITSM) practices in the banking sector, focusing on service quality improvement through systematic monitoring, reporting, and the application of ITIL frameworks. Drawing from a professional experience as a service manager at GFT Italy, managing Application Development and Maintenance (AD&M) services for a bank, this work bridges theoretical ITSM concepts with practical implementation challenges in a highly regulated financial environment. The research begins by establishing the theoretical foundations of service management, exploring its main models, and examining their specific application in banking contexts where operational reliability, regulatory compliance, and cybersecurity are a focus aspect. It provides comprehensive analysis of the ITIL 4 framework, detailing its Service Value System, Service Value Chain, the four dimensions of service management, and service management practices including incident management, problem management, change management, and service level management.