Pediatricians are medical doctors considered primary care providers, also known as the gatekeepers to the healthcare system, who manage the complete health care needs of children from birth to young adulthood. This primary care doctor delivers the broad spectrum of acute and chronic healthcare services and often coordinates care provided by other specialists. Pediatricians are broadly trained in the diagnosis and treatment of tumors, infections, and diseases affecting all organ systems. They are also trained in the essentials of primary care, providing preventive care, including routine evaluation, vaccinations, risk assessments and screening laboratory and imaging tests, and counseling on overall mental and physical health, substance abuse, and cultivating a healthy lifestyle. The Pediatrician deals with physical, emotional, social, and environmental influences on the developing child and with the impact of disease and dysfunction on development.