This paper introduces a conceptual framework for evaluating different supply chain structures in the context of modularization and postponement. In the analysis, modularization is linked to inbound logistics as the combination of different components (or modules) allow for the assembly of the final product. Postponement, however, corresponds with the outbound logistics since it is through the distribution function that customers' specific demand is satisfied. Given this perspective, a taxonomy is introduced and a corresponding framework for the characterization of four supply chain structures, defined according to the combined levels of modularization and postponement, is developed: rigid, postponed, modularized, and flexible.