Single Sign-On (SSO) platforms such as Okta, Microsoft Entra ID, and JumpCloud help organizations streamline authentication by allowing users to log in once and securely access multiple applications. In practice, one major success is improved user experience and reduced password fatigue, as employees can access all their tools without managing multiple credentials. Challenges often include integrating legacy or custom applications that may not support modern SSO protocols and ensuring consistent user adoption across the organization. Teams typically address these issues by prioritizing applications with standard SAML or OIDC support, providing training and communication to end users, and gradually rolling out SSO in phases to identify and resolve integration problems. Additional strategies like centralized access policies, automated provisioning, and monitoring login activity help maintain security while easing adoption and minimizing disruption.