A questionnaire designed to identify the factors that influence the resolution of ethical dilemmas was returned by 230 (57% of the total) Massachusetts (USA) pediatricians. The decision to recommend surgery for an infant with Down''s syndrome with duodenal atresia when the parents had refused surgery was influenced by religious affiliation, religious activity and sex. Of those favoring surgery, 40.2% would pursue a court order. The decision to recommend surgery for an infant with severe meningomyelocele when the parents'' position was not stated was influenced by age, religious activity and specialization. When the parents'' wishes were expressed, the majority of the peditricians modified their decision in accord with these wishes. In response to general ethical questions, 79.6% of all pediatricians thought that parents should have the right to withhold consent for surgery. Equal numbers thought that psychosocial reasons justified withholding lifesaving procedures. Among a variety of factors, they thought willingness of the parents to care for the child would influence the decision to take heroic measures. There were 90.4% who thought that ethics should be part of medical education; 55.7% indicated this need throughout their careers.