Part one sets out the theory of rhizoids as social/technical networks underpinning the stewardship of resources. Rhizoids are defined as coherent behaviour patterns involving flows, stows, stocks and transformations. The philosophy of Vollenhoven and Dooyeweerd is used as a theoretical framework for the development of the concept. The economic significance of rhizoids is illustrated on the basis of Eucken's economic morphology. In the dairy industry the milk flow is produced, transformed and transported by means of a set of connected stows and flows of natural resources, knowledge, equipment, finance and information. This rhizoid is managed in a variety of ways. New Zealand based farmers, producers and exporters have only limited control over the whole of their rhizoid. Part two shows how the NZ dairy industry groped towards the formation of the present rhizoid. Technical innovations were decisive factors. Data on productivity development suggests questions about the sustainability of the present rhizoid, especially in the light of international technical and economic developments in the dairy industry. The industry is forced to innovate in order to survive.