A modern management theory that can be applied to health care is the open system theory of management. The open system theory of management focuses on changes in an environment. The health care system exists as its own social system. This is demonstrated by the hierarchical nature of care providers. For example, unit clerk, nurse, doctor. In the open system theory, a feedback loop exists causes energy, or change, within the organization. Each part of the system is dependent on the other. In a hospital setting, this can be demonstrated with caring for a patient. The medical staff is dependent on the nursing staff. The nursing staff is dependent upon the pharmacy for correct medication administration. The pharmacy is dependent upon health information technology to accurately record the medication.