SAML metadata plays a critical role in ensuring secure and reliable Single Sign-On (SSO) integrations. Misconfigured or outdated metadata can cause authentication failures, leading to downtime and security breaches. Common pitfalls include expired certificates, stale or hardcoded metadata files, mismatched Entity IDs or ACS URLs, unsupported or incompatible bindings, misconfigured signing and encryption flags, and version conflicts. To avoid these issues, it's essential to implement failover metadata sources, use metadata aggregators, monitor and alert on metadata and SAML failures, automate metadata updates, handle metadata version conflicts, and maintain a rollback strategy. By taking a proactive approach to managing SAML metadata, teams can ensure their SSO integrations are resilient by design and minimize the risk of authentication failures.