This chapter, titled Economic Factors in Agriculture and authored by Elizabeth “Izzie” Gall and Barbara Laff, provides an overview of some important economic and legal factors in the agricultural market. Agricultural supply and demand are complex concepts, each responding to a range of factors. Supply is impacted by the cost and availability of inputs, expected marginal return of each seed, and unpredictable changes in growing conditions. Legal recognition of plants as intellectual property further alters input considerations, as farmers must carefully handle all seeds or risk infringing patent law. Demand can fluctuate with health and safety trends as well as with other factors. In a free market, producers and consumers interact based only on supply and demand. However, the signal of demand is often complicated by time delay, market distortions, government interventions, and ecological factors, making it difficult for farmers to know which outputs are most valuable to the end consumer and which inputs are worth investment and risk. The market is further complicated by treatment of some crops as commodities rather than individual products. Crop diversification is effective protection against poor weather, low yields, and other random factors, but farm consolidation and government interventions like subsidies often favor specialization and monocropping.