THE ROCKEFELLER UNIVERSITY 1230 YORK AVENUE NEW YORK, NY 10021 July 20, 1979 JOSHUA LEDERBERG PRESIDENT Dr. C. E. Gordon Smith Dean London School of Hygiene and Tropical Medicine Keppel Street (Gower Street) London WClE 7HT Dear Dr. Smith: Thank you for your letter of June 27th and its invitation to the Heath Clark Lectureship. I am very much interested in the work of the London School and it is with some regret that I have to say that it is not very likely that I can fit the lectureship into the schedule of my duties at the University here. As you are well aware, the Rockefeller University has also had a long standing tradition of research in parasitology. Professor William Trager will be retir- ing within the next two years and I have already ap- pointed a search committee to seek an outstanding figure to sustain that research tradition. I would be very happy to have your own suggestions of possible candidates who could combine a concern for research on the organisms of parasitic diseases with the ap- proaches of modern cell, molecular, and immunobiology. oshua Lederber Encl.