This handbook discusses the principles governing the adjustment of high speed planers. It summarizes basic principles, which if observed will ensure adequate performamce in terms of production and quality, as well as maximum service life of planer equipment. Furthermore, it provides a new method for conducting a diagnostic evaluation of planer adjustment and introduces a new concept for the optimization of planer depth-of-cut.The techniques and information contained in this handbook are intended primarily for millwrights, planer operators, quality control personnel and managers of high production softwood planer mills. Several techniques and recommended practices also apply to hardwood planer operations and to all other planer and moulder operations.