Officials in the US Department of Health and Human Services (HHS; Washington, DC) released revised guidelines on xenotransplantation late in May, reaffirming the need for the FDA to continue its regulatory oversight of this field. The guidelines specifically call upon blood centers and other clinics to reject blood or organ donations from xenotransplant recipients and their close contacts, such as family members, to reduce the risk of transmitting novel pathogens from animal sources. They also call for more stringent procedures in handling animals whose organs are used for transplants, such as use of surgery to deliver animals at birth, breeding of closed herds in specialized facilities, and active monitoring of those herds for evidence of infectious agents. In addition, there will be extensive counseling of patients who receive xenotransplants, who will essentially be required to cooperate with long-term surveillance programs. Following another recommendation within the revised guidelines, HHS is establishing a new public advisory committee, the Secretary's Advisory Committee on Xenotransplantation, to discuss both scientific and ethical concerns that arise from this area of medical research; the new committee will meet initially sometime this summer.