Reorganization

Definition: a Reorganization is the act or process of changing or restructuring a firm's operations for various reasons, ranging from concentrating on core activities and outsourcing peripheral activities to repositioning a business to dealing with corporate changes such as mergers and acquisitions, to merely improving efficiency or cutting costs.
A reorganization often includes changes to departments, business units and employee roles, and often includes significant employee layoffs.

More on reorganizations. More on organizational structure: Formal Organization, Informal Organization, Organization Chart.