Who is responsible for defining metrics for change management?

In ITIL, the process owner is responsible for the overall design, performance, integration, and improvement of their assigned process, and defining metrics is a core accountability of that role. The process owner ensures the process is fit for purpose and produces desired outcomes, which requires setting the measurement criteria. No other role has this specific design-level accountability for a given process.

The Change Advisory Board is an advisory body that evaluates and approves change requests; it does not own or govern the change management process itself.

The service owner is accountable for a specific IT service delivered to customers, not for the internal design or measurement framework of the change management process.

The continual service improvement manager coordinates improvement initiatives across the organization but does not define the operational metrics for individual process owners.