The addition of explicit resource links is an optional approach in Critical Chain planning. Explicit links effectively create a task dependency where there was only a resource dependency. If the resource situation changes during project tracking, the link may no longer be valid and could delay the successor task unnecessarily. When explicit links are used, the project manager has the added responsibility of reviewing the validity of specific links based upon any changes in resource assumptions during tracking. If a specific link is no longer valid, it can be deleted using this command.