The Archbishop is the top of a diocese or archdiocese within the Catholic Church. He’s liable for the non secular and administrative management of his diocese or archdiocese. As an indication of respect, it is very important handle the Archbishop in a proper and respectful method.
The proper approach to handle the Archbishop is “Your Grace.” That is adopted by his final title. For instance, if the Archbishop’s final title is Smith, you’d handle him as “Your Grace, Archbishop Smith.”