This paper explores changes in organizational structure and distinguishes between units' origins. Unit reconfiguration is the addition of units to, deletion of units from, and recombination of units within the firm. This study compares the reconfiguration of internally developed vs. acquired units, explores what forms of unit recombination are common, and observes whether firms pursue recombination before divestiture. Theoretical support is drawn from the dynamic capabilities perspective, research on modular organizational systems, and strategy–structure literature. The findings are that acquired and internally developed units serve different roles in the process of change, and that firms perceive reconfiguration to be beneficial. Copyright © 2006 John Wiley & Sons, Ltd.