Ambulatory care, also known as outpatient care, refers to medical services provided on an outpatient basis without admission to a hospital or other facility. It includes diagnosis, observation, consultation, treatment, intervention, and rehabilitation services, and can be performed in various settings such as medical offices, clinics, ambulatory surgical centers, and urgent care clinics. Ambulatory care services can be delivered by a multidisciplinary team of health professionals, including physicians, nurse practitioners, nurses, pharmacists, occupational therapists, physical therapists, speech therapists, and other allied health professionals. Many medical investigations and treatments for acute and chronic illnesses and preventive health care can be performed on an ambulatory basis, including minor surgical and medical procedures, most types of dental services, dermatology services, and many types of diagnostic procedures. Ambulatory care services represent the most significant contributor to increasing hospital expenditures and to the performance of the health care system in most countries, including most developing countries.