How do you implement CI/CD pipelines with Docker?

Docker CI/CD pipeline implementation: 1) Basic pipeline stages: Build Docker image, Run tests in containers, Push to registry, Deploy to environments, 2) GitLab CI example with stages build, test, deploy using docker build, docker push, docker run for tests, docker service update for deployment, 3) GitHub Actions example with checkout, build image, run tests, deploy steps, 4) Multi-stage pipeline: FROM node:16 AS test with COPY, RUN npm ci, RUN npm test, then FROM node:16-alpine AS production with COPY --from=test. Best practices: Use specific image tags, Implement security scanning, Cache dependencies, Parallel test execution, Blue-green deployments.