Letter to Dr C.A Ludlam- Haemophilia Department Royal Infirmary Edinburgh from J. Craske- Consultant Virologist regarding AIDS and Haemophiliacs Re-Paper prepared for MRC Hepatitis Vaccine Working Group reference to US Centre for Disease Control (C.D.C) who knew of five haemophiliacs in the USA who have contracted AIDS. US hypothesis; contraction through contaminated factor VIII. Meeting of working party suggested to decide what investigations need to be undertaken in British haemophiliac population.