The need to make the best use of wood supplies, conserve energy, and reduce the costs of pollution abatement has stimulated research to improve the yield, accelerate the rate, and reduce the odoriferous nature of kraft pulping. Because the structure of lignin is imperfectly understood, the quest for reagents which can accelerate delignification has been handicapped. In contrast, because the structure and reactions of cellulose and other wood polysaccharides are known, deductive methods have been applied in the search for reagents which can protect these polymers from alkaline degradation and thus improve pulp yields. The discovery of the dramatic accelerating effect of anthraquinone on alkaline delignification can, in fact, be traced back to a series of investigations which began with a search for reagents capable of inhibiting the alkaline degradation of cellulose. Against this background, research on pulping additives in reviewed, with particular reference to the current status and potential of catalytic accelerators in alkaline pulping.