Strategic business unit

Strategic Business Unit or SBU is understood as a business unit within the overall corporate identity which is distinguishable from other business because it serves a defined external market where management can conduct strategic planning in relation to products and markets. When companies become really large, they are best thought of as being composed of a number of businesses (or SBUs).
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a separate operating division of a company with some degree of autonomy; commonly referred to as an SBU.

any product, group of products, categories of products, departments, divisions that might be seen as a profit centre. The SBU can be analysed using the BCG matrix, the PLC etc.(see Portfolio Management).