# Software as a Service
**Aliases:** SaaS
**Entity class:** Cloud software delivery model
## Definition
**Software as a Service (SaaS)** delivers an application as a managed service rather than as customer-operated software installed independently in each environment. Government SaaS still requires authorization, identity, access, data-governance, logging, and contractual controls.
## Relationships
- **acquisition category:** [[wiki/Commercial Off-the-Shelf Software|COTS]] may be delivered as SaaS.
- **security baseline:** [[wiki/FedRAMP High|FedRAMP High]] where high-impact data is involved.
- **integration:** [[wiki/Application Programming Interface|APIs]] and web services.
## Sources / Provenance
- [NIST — Cloud Computing Definition](https://csrc.nist.gov/pubs/sp/800/145/final)