Under Title 21 of the Code of Federal Regulations, blood and blood products must be “labeled” with appropriate information regarding uses, dosage, and administration instructions (just like the FDA requires for package inserts for drugs). If you have ever looked at a unit of blood, it is pretty easy to see that there is not enough room on the label that is actually on the bag for all of that stuff. The solution is the “Circular of Information for the Use of Human Blood and Blood Components”, a document developed by AABB, the Department of Defense, and the two major blood collection organizations in the United States: American Red Cross and America’s Blood Centers. This very large document accomplishes the goals listed above, and must be made available to all persons involved in transfusing blood. The current version (updated in 2017) is available on the AABB web site. Note that a similar document for cellular therapy products such as peripheral stem cells and bone marrow transplants is also available from AABB.