Livestock manure and crop trash contain nutrients that can be processed as plant or animal food. Modern agriculturalists or practitioners often treat them as wastes and dispose of them into the surrounding environment, favoring the purchase of commercial fertilizers or feeds. However, in recent years a combination of changes has set the stage for reexamining such practices; namely, increased cost of commercial fertilizer and livestock feed, increased costs of waste disposal due to regulation, and improvements in waste management technology. There were approximately 11,300 head of dairy cattle on Oahu in 1976, annually generating about 165,000 tons of raw manure. This manure contains considerable amounts of plant nutrients which could be used by the pineapple industry. Most of the manure is not utilized and, instead, is disposed of at considerable cost to the dairy industry. The waste also creates potential pollution problems in certain coastal areas of the island. There are about 5,000 acres of pineapple land harvested annually on Oahu, generating about 250,000 tons of post-harvest plant material (trash). Most of the trash is harrowed down, field dried, and burned on the field, with the remains plowed into the soil as fertilizer. Considerable nutrients are lost and pollution is created because of trash burning. With the cooperation of the Hawaii state government, considerable interest has been generated by dairy farmers and the pineapple industry in the use of byproducts to substitute for increasingly expensive imported feed and fertilizer. In 1976, a private cooperative was established to chop and remove the post-harvest pineapple plants and sell them to dairy farms as a roughage feed. This paper presents an analytical framework for investigating the integrated use of agricultural byproducts. An example is used to illustrate the workings of this framework. The empirical results of an actual case study conducted in Hawaii are presented as a demonstration of the operational potential to the real world situation. Finally, the framework is extended into a generalized byproduct use model. The model accounts for both efficiency and distributional considerations. Conceptual Model