This chapter focuses on building and managing stateful applications in Kubernetes with an emphasis on data persistence and lifecycle management. It begins by explaining container filesystem layers, differentiating between system and application containers, and demonstrating Kubernetes’ role in orchestrating real-world web applications. The use of kubectl is detailed, covering namespaces, contexts, object management, and advanced filtering with JSONPath to efficiently organize environments. Pods are examined as the core execution units, including resource allocation, lifecycle control, and multi-container designs with shared storage. Labels, annotations, and selectors are introduced as powerful tools for metadata management and grouping objects. Service discovery methods, ReplicaSets for scaling, DaemonSets for distributed workloads, and Jobs for batch processing are presented with practical use cases. The chapter also addresses configuration management through ConfigMaps and secrets, while deployments are shown as the foundation for managing updates. Finally, persistent data challenges are explored, along with strategies to ensure reliable storage, highlighting Kubernetes’ ability to balance scalability with durability.