PREFACE Each year@ more than $20 billion is spent in the United States to construct asphalt pavements for highways and airports. Asphalt paving contractors@ public agencies@ and the pavement research community share concerns about the problems of properly constructing these pavements. Pavement experts agree that highway and airport agencies and their pavement contractors not only have difficulty incorporating research findings into field practice@ but also have difficulty in consistently applying proven procedures from earlier research experience. Training is a problem in such a decentralized industry@ where many producers and contractors operate on too small a scale to make long-term investments in personnel development; and@ as a result@ the knowledge and experience of field personnel is often not up-to-date. A working group of industry@ government@ and academic officials assembled by the Transportation Research Board (TRB) agreed that a step towards addressing some of these problems would be the development of an asphalt paving handbook@ widely accepted by major segments of the paving industry. Field manuals and handbooks have been available from many agencies@ but none has been adopted by all major industry segments; and@ as a result@ personnel from contractors and specifying agencies may be confused by conflicting recommended practices. A single manual could reduce this confusion and assist in the promulgation of good practice based on available research and experience.