If you are referring to product changes, I have found that it is extremely helpful, arguably essential, to have a really robust form used for the process. Have the form walk you through as many different areas of impact to consider as possible. People will not always break out the SOP every time. But they will HAVE to use the form. Build in fields to be filled out that address things like regulatory impact, customer notification, stock disposition, etc. That way they are inherently considered and either addressed, or the rationale for nonapplicability included. Put sign offs where they are needed and make different sections of the form that correspond to the flow of the process, i.e. one for the change plan, one for execution of the change, one for effectiveness verification. This approach has helped us tremendously.