SaaS security refers to the strategies, tools, and practices used to protect SaaS applications and their data from threats. It encompasses access management, data encryption, activity monitoring, and compliance enforcement. SaaS security is uniquely challenging due to the shared responsibility model, where SaaS providers secure the infrastructure, but customers must secure user access, configurations, and data. Organizations achieve strong SaaS security by adopting tools like CASBs, SSPM platforms, and robust identity governance systems.