DEDICATION This report is dedicated to Dr. Shields Warren, who died during the past year. The many accolades received by Dr. Warren during his illustrious career need not be reviewed here. He was a leading authority on the pathological effects of ionizing radiation on human beings and was also highly regarded in the field of thyroid pathology. He was the first director of the Division of Biology and Medicine of the Atomic Energy Commission, and he played an important part in the examinations of the atomic bomb survivors in Japan. Following the fallout accident in the Marshall Islands, we turned repeatedly to Dr. Warren for advice, particularly concerning the pathological aspects of the thyroid lesions. He strongly supported our program and gave generously of his time and talents to help us. He reviewed countless sections of thyroid tissues from the Marshallese and provided valued opinions. Dr. Warren was a dedicated physician. scientist, and educator. His personal warmth, enthusiasm, sincerity, and encouragement endeared him to all of us. He was a true and loyal friend and we shall sorely miss hia. ~ tii-