Serverless computing abstracts infrastructure and scales automatically, but it also introduces new security responsibilities for developers and security teams. In cloud environments powered by AWS Lambda, Azure Functions, or Google Cloud Functions, security shifts toward code quality, identity, and data handling. Developers must apply least‑privilege roles so each function can only access the resources it needs, and avoid embedding secrets in function code by leveraging cloud‑native secret‑management services. Input validation and sanitization are critical, as serverless endpoints are often exposed to the public internet via API gateways that must enforce rate limiting, authentication, and request‑validation rules. Continuous monitoring and observability tools track function invocations, error patterns, and unusual traffic, flagging potential abuse or exploits. By combining secure coding practices, strict identity policies, and runtime monitoring, organizations can safely unlock the agility and cost‑efficiency of serverless while maintaining strong cloud‑native security posture.