As the below image suggests, business capabilities define "what" a business does, not the "why" or "how." Business capability mapping is about structuring the functional capabilities of a business hierarchically. Business capabilities are a good way to connect the vision of various stakeholders to the execution value chain. Capabilities are a great communication tool across the organization, and breaking down capabilities to the appropriate level of granularity can help bridge the gap between different functional and IT groups. As illustrated below, taking a holistic view of the business unit or organization, the Business Unit head and corporate strategy team together define the vision for the business unit.