Kubernetes security is crucial due to the complexity of microservices it introduces. Key practices include limiting cluster access, implementing Role-Based Access Control (RBAC), securing the API server, using Transport Layer Security (TLS) for secure network communication, and employing network segmentation through network policies and namespace isolation. Monitoring and auditing can be achieved by configuring audit logs and events API. Secure images can be obtained from trusted sources and scanned for vulnerabilities. Keeping the cluster up-to-date with rolling updates and regular upgrades is also essential.