This document summarizes best practices for container security. It begins with case studies and hygiene factors like fully patching images and scanning images before pushing them to a registry. It then discusses DevSecOps practices like architectural reviews, automation, and training. Recommendations are provided for tools to address image vulnerability scanning, source code scanning, run-time security, compliance, and comprehensive security. Finally, it discusses platform-specific considerations for AWS, Azure, DockerHub and others regarding registry access control, vulnerability scanning, and run-time protection tools.