A health system consists of all organizations, people and actions whose primary intent is to promote, restore or maintain health. The current healthcare system, which is very complex and fragmented, does not ensure timely access to care, lacks coordination among multiple providers, is inefficient in its use of resources, and pose patient safety problems. Healthcare systems engineering uses systems engineering tools such as probability and statistics, data mining, simulation, optimization, and human factors engineering to improve access, efficiency, effectiveness, quality and safety in healthcare delivery systems. A systems approach is used to analyze and solve problems at patient, care team, organization, and population levels. Several healthcare settings such as hospitals, outpatient clinics, and long-term care facilities, and the interactions between these settings are considered.