Phlebotomy is the practice of drawing blood from a patient for the purpose of laboratory analysis or blood transfusion. It is a skill performed by trained professionals known as phlebotomists.

The procedure typically involves a small needle being inserted into a vein, usually in the arm, and the collection of a specific amount of blood into one or more vials or tubes, these tubes are labelled with the patient's information and sent to a laboratory for analysis. Phlebotomy can be done in a variety of settings, such as hospitals, clinics, and diagnostic laboratories.