Before beginning the performance management process, boards must have a good principal performance review policy in place and both boards and principal must be aware of, and follow, that policy.
NZSTA provides a performance review policy template, see B9 Principal performance management policy of the Governance framework 2018.
New board members and principals must be given a copy of the policy and process and boards must ensure they follow this policy during the annual agreement and review cycle.
Board policy can be reviewed and amended at any point.
The whole board is the "employer entity" and should be involved in the management of the principal. It may be practical that the management of the performance process be delegated (in writing) to a smaller committee, for example the board chair and one or two members with skills or interest. However, the whole board is still responsible and accountable for principal performance management.
Therefore, the policy should not have a provision for process or report to be confidential to a sole reviewer and principal only. Rather, the process and report should be confidential to the board (and their consultants) "in committee".