ABSTRACT Complexity in design causes iteration which can be value-adding or wasteful. Wasteful iteration, called rework, may stem from inefficient information flow in design. This paper focuses on the structural complexity of information flow, and on the identification of root causes of the resulting rework. We propose that one can identify root causes for rework in the design phase of a project by (1) making actual information flow transparent and by (2) comparing actual information flow to planned information flow. After identifying misalignments between actual-and planned information flow, one can find their root causes, and then address those causes in order to reduce rework in design. We use a Multi Domain Matrix to deduce actual ('As is') and planned ('Should') information flow and then apply the Delta-Design Structure Matrix to compare the structures of the 'Should-' with the 'As is' perspective. The proposed hypotheses, "Comparing structural complexity between the 'Should-' and the 'As is' perspective helps to identify misalignments" and "Reduction of misalignments between actualand planned information flow reduces rework in design" were tested during the detailed design phase of a project. The Multi Domain Matrix and Design Structure Matrix were successfully applied: comparison of structural complexity aided in making actual information flow transparent and in reducing rework