When you start the Copy/Monitor tool, select Use Current Project, and then select Monitor, you can establish relationships between elements in the current project, and monitor changes to the elements. When an element changes, a warning alerts you of the change.
For example, use this method to monitor 2 grid lines. If a grid line is moved, a warning alerts you so that you can adjust the other grid line, if needed. See Monitoring Elements in the Current Project.
You can also use this method when implementing Copy/Monitor in a workshared project. See Copy/Monitor and Workshared Projects.