Single Sign-On (SSO) allows users to access multiple systems with a single set of credentials, enhancing both convenience and security when implemented with care. In this episode, we explain how SSO functions by relying on a centralized identity provider that issues authentication tokens to various applications, removing the need for users to log in repeatedly. We explore the protocols that power SSO, including Security Assertion Markup Language (SAML), OAuth 2.0, and OpenID Connect, and how each supports different use cases like web-based applications, APIs, or mobile authentication. While SSO reduces the burden of managing passwords, it also introduces risk—if the identity provider is compromised, access to multiple systems may be affected. To mitigate this, we discuss the use of multi-factor authentication (MFA), session timeouts, and token validation to reinforce trust across systems. SSO is a powerful access management tool—when backed by strong identity proofing, encryption, and oversight.