Discusses runway conditions at national system airports & provides cost estimates for maintaining & rehabilitating these runways over the next 10 years. The report addresses: (1) the current condition of the nation's airport runways, (2) the likely cost of rehabilitation & preventive maintenance for these runways over the next 10 years; (3) FAA's basis for setting priorities among requests for grants for runway rehabilitation & maintenance, & (4) the results of the demonstration project to address concerns that a lack of funding was hampering runway maintenance at small airports. Charts & tables.