What is an Organizational Structure
An organizational structure is a way of describing the relationships among groups and individuals in an organization. At the heart of an organizational structure are two things: roles/responsibilities and communications/accountability. Roles and responsibilities refer to what a person or group does, and communications/accountability involves the relationships that a person or group needs to hold in order to perform their job. It is important to note that even egalitarian or "flat" structures require some kind of relationship in order to perform effectively.
These roles and responsibilities often fall under the three "Ps": "purpose," "people," and "process." A purpose role would describe a group or division through some kind of function. For instance, a "circulation" department is a functional group because people are expected to ensure the effective circulation of materials. A people role focuses on a specific group. "Youth services" would be a good example of a people-oriented role. A process role (sometimes called a "corporate" role -- meaning that their job permeates throughout an organizational body) focuses on coordinating among the different function and people roles. Human Resources is probably the most recognizable "process" role.