EvidenceSheet
NIST SP 800-53 Rev 5 · SA - System and Services Acquisition

SA-9(3) External System Services | Establish and Maintain Trust Relationship with Providers

Establish, document, and maintain trust relationships with external service providers based on the following requirements, properties, factors, or conditions: organization-defined security and privacy requirements, properties, factors, or conditions defining acceptable trust relationships.

Source: NIST SP 800-53 Rev 5, SA-9(3). The statement above is our statement of the clause, read from the published text and cited so you can check it against the official text, not the instrument verbatim. Open NIST SP 800-53 Rev 5 in the compliance library.

Base controls and their enhancements. Which apply follows the baseline you are assessed against (for example FedRAMP Moderate or High, or the low, moderate and high baselines of SP 800-53B). Text in square brackets is a parameter your organisation sets.

9
artefacts
0
held by a system
0
at each review
hard
to go live
Policy repository / GRC workspace
where the evidence lives
teal = a system already holds it · olive = produced at each review. To go live: easy when half or more of the artefacts are already held by a system, moderate from a quarter to a half, hard below a quarter.

These are the artefacts auditors commonly ask for on this requirement, our guidance rather than text from the standard. Your assessor decides what is sufficient in your context, and asks for samples across the period when a report covers one.

system holds itEvidence a system already holds

none for this control

periodic reviewEvidence produced at each review

none for this control

governing documentDocuments that govern the control

  • System and services acquisition policy · Policy repository / GRC workspace
  • System and services acquisition procedures · Policy repository / GRC workspace
  • Acquisition contracts for the system, system component, or system service · Vendor register / contract repository
  • Acquisition documentation · Document repository
  • Solicitation documentation · Document repository
  • Service level agreements · Vendor register / contract repository
  • Memorandum of understanding · Document repository
  • Memorandum of agreements · Vendor register / contract repository
  • List of organizational security and privacy requirements, properties, factors, or conditions for external provider services · Policy repository / GRC workspace

First move

No system holds this evidence for you: it is people and documents. Reminders and routing to the owner still save time. Put the document under version control with an owner and review date, and log each review as a record with reviewer and date.

Common gaps auditors find

Do this for your whole sheet

Paste the rows you run your controls from and get this mapping for every control at once, with the periodic-review ones flagged and a first move per row. No account for the first run.

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SA-9(2) External System Services | Identification of Functions, Ports, Protocols, and Services · SA-9(4) External System Services | Consistent Interests of Consumers and Providers