Micro-Foundations of Product Interfaces and Their Implications on Product and Organization Design

Despite the importance of product interfaces for product development organizations, little is known about how product interfaces manage component interdependencies. In order to answer this question, we make one of the initial attempts to define micro-foundational interface properties by building on and extending the seminal works of Simon (1962) and Parnas (1972) on which the literature on modularity and product architecture is built. Rather than being simple linkages, we show that interfaces exhibit a core-periphery structure by underlining the importance of functional interdependencies managed by interfaces in addition to structural interdependencies. Our theoretical reasoning illustrates that the differentiation and integration role of interfaces and the functional and structural interdependencies managed by product interfaces inform three interface properties: structural thickness, functional thickness and conductivity of interfaces for the interface core and periphery. We illustrate the congruence of these properties with examples and discuss their implications for product design, organization design and the relationship between product and organization design, the so-called mirroring hypothesis.