The U.S. Secretary of the Interior defines <b>historic preservation</b> as "retention of all historic fabric through conservation, maintenance, and repair." This category also includes resources for the related practice of <b>rehabilitation</b>, which includes replacement of severely deteriorated elements of the structure. This category is for architects, planners, craftspeople, and materials manufacturers whose primary speciality is historic preservation and rehabilitation and who routinely serve a national, international, or broadly regional clientele.