Business portfolio analysis is the process of determining which lines of business to be in. A business line, also called a strategic business unit (SBU), is a distinct business having its own customers that is managed independently of other businesses within the corporation. The primary objective of corporate portfolio management (CPM) is to make strategic decisions about the allocation of resources among SBUs.
A popular approach to CPM is to create a Boston Consulting Group (BCG) Growth-Share Matrix for each line of business or product line as a business strategy. A BCG matrix contains four cells: Cash cows generate more resources than they need, so the profits are used to fund question marks and stars. Question marks are entries into new businesses.
Stars are question marks that succeed. Dogs are doing poorly and are usually sold or liquidated. A company in a single line of business cannot conduct a business portfolio analysis.