Northwell Health ( Northwell ) is more than just a healthcare system . As the largest private employer in New York , the company employs more than 12,000 credentialed physicians , including approximately 4900 doctors and 18,900 nurses . With a combined footprint of 21 hospitals and more than 850 outpatient facilities , Northwell provides care to two million patients annually – including approximately 19,000 new cancer patients – more than any other healthcare provider in the state and delivers more than 30,500 babies annually , accounting for 15 percent of all the births in New York . Northwell also boasts one of the largest medical residency programs in the US and operates the largest hospital-based laboratory in North America .