Service catalogs have evolved into essential tools within platform engineering, providing a centralized metadata hub for managing microservices and applications in modern development environments. Unlike traditional IT catalogs, these modern service catalogs help navigate the complexities introduced by cloud-native technologies, offering a unified interface that automates updates and provides real-time data. They improve developer productivity and satisfaction by streamlining the discovery and management of service ownership, dependencies, and compliance requirements, while also optimizing resource costs and aiding in application security management. Companies like TransferGo, Libertex Group, and Cybersixgill have successfully implemented service catalogs to enhance efficiency and collaboration within their internal developer portals. By offering a comprehensive view and enabling self-service capabilities, service catalogs facilitate better decision-making and resource allocation in software development.