As businesses increasingly adopt multi-cloud strategies to improve cost, performance, and availability, managing dispersed infrastructure across many providers becomes a crucial challenge. Infrastructure as Code (IaC) emerges as a key paradigm, allowing for automation, version control, and consistency in infrastructure provisioning and administration. This article provides a complete examination of IaC best practices for multi-cloud settings, focusing on modular architecture, tool standardization, governance, security integration, and automation via CI/CD pipelines. Terraform, AWS CloudFormation, and policy-as-code frameworks like OPA are all appraised for their use in cross-cloud orchestration. The paper uses case studies and practical examples to demonstrate how firms can streamline deployments, decrease operational risk, and assure regulatory compliance in complex enterprise systems. These insights are intended to assist DevOps and cloud engineering teams in creating durable, scalable, and secure multi-cloud infrastructures.
