In meicine venipuncture or venepuncture (also known as phlebotomy, venesection, blood draw, drawing blood or taking blood) is the process of obtaining a sample of venous blood. Usually a 5 ml to 25 ml sample of blood is adequate depending on what blood tests have been requested. In many circumstances it will be done by a phlebotomist, although nurses, doctors, some EMTs, paramedics, other medical staff and chiropractors are also trained to take blood.