Only Service Level Agreements (SLAs) provide a mechanism where the cost of nonconformity will be accounted for. Therefore, any service commitment, whether internal or external, should be documented in an SLA.
The SLA should describe the services and service commitments at an appropriate level of detail such that there is no ambiguity as to what is to be provided and what therefore constitutes a violation of the SLA. (Legal) Terms and Conditions should follow a similar approach.
The SLAs should be maintained by the agreed frequency of regular planned reviews by the parties involved to ensure that they:
1) Are up-to-date and appropriate
2) Match the infrastructure design and set-up
3) Address the changed business needs
4) Resolve major service issues
Any changes required should be managed by a change management process.
