What is SSO (single sign-on)?

In practice

The standards are SAML and OpenID Connect, and supporting one of them is a modest piece of work if planned and an awkward one if bolted on after the user model has been built around local accounts. If you expect enterprise or public-sector customers, design for external identity from the beginning even if you launch with passwords.

Where it fits in a build

Necessary for internal tools at any organisation with central IT, and for any product sold to enterprises. Optional for products sold to individuals or very small teams.

Common mistakes

• Treating SSO as authentication only and ignoring provisioning, so accounts are created centrally and never removed.
• Charging for SSO as a premium tier, which security teams increasingly treat as a red flag.
• No break-glass administrator account, so an identity provider outage locks everyone out.

Related terms

• Role-based access control (RBAC)
• Least privilege
• SaaS

Working on something that involves this?

ASTACKRA designs and builds AI systems, automation and custom software for businesses that need technology shaped around their own workflow. If this term turned up in a proposal and you want a straight answer about whether it applies to your situation, ask us — no obligation, and we will tell you if the answer is no.