Compared to painters of '400 Florence, the costs of materials and production for sculptors were significantly higher. Much has been written about demand and the taste of the patron as reflected in the types of projects they commissioned. Yet there must have been the equal but opposing force of supply. To mitigate the high cost of materials, labor and transport, sculptors had to choose materials and seek production processes that increased profit margins and reduced the labor required of the master's hand. While personal passion and commission competition are among the motivators normally seen to engender innovation, there evidently was the less lofty concern for the cost effectiveness of production. And this in turn would stimulate the craving for, and the evolution of, new technologies, and by the end of the '400, a keen savvy for branding and marketing the objects of supply. Using examples from the practice of Ghiberti, Donatello, Luca della Robbia and Michelangelo, this is an examination of the ways in which '400 sculptors successfully negotiated the emergent art-as-commodity market.