Joined by my new "Ask the BBGuy" co-host, Dr. Heidi Shafi, I take a detailed look at Transfusion-associated Graft-vs-Host Disease (TA-GVHD). This transfusion complication is by far one of the most dangerous, fatal in over 90% of cases. I start from the basics and outline the details of TA-GVHD, and discuss the implications of a game-changing 2015 article on the topic.