The D polypeptide is a highly immunogenic antigen and can cause a clinically significant antibody response in individuals who are D-negative. One of the most effective immunological interventions in clinical medicine is the prevention of hemolytic disease of the fetus and newborn (HDFN) by the prophylactic administration of anti-D IgG to at-risk mothers. Anti-D has also been highly effective in treating D+ individuals with immune thrombocytopenia (ITP). Anti-D immune globulin is a pooled IgG purified product obtained from D immunized donors and therefore carries the risk of transmission of emerging pathogens. Efforts to replace this highly effective polyclonal product with recombinant antibodies or peptide therapy are underway. The focus of this educational program will be to educate attendees on the latest research focusing on understanding the mechanisms of action of anti-D in both ITP and HDFN. One speaker will discuss some of the latest research that has been done on how anti-D might work in ITP. Another speaker will discuss potential mechanisms of action of anti-D in Rh prophylaxis. The final speaker will educate the audience on how T cells are involved in the immune response against the D antigen and discuss recent advances in novel methods to perhaps prevent HDFN utilizing peptide therapy.