Four cases of "delayed" sudden infant death are described in infants, who were found lifeless and were resuscitated, but did not regain consciousness. Circulatory failure occurred 20-48 hours later. In these cases, one could expect an accentuation of such lesions which might have caused the collapse. Among the cases there were bronchopneumonia, areas of coagulative myocardial necrosis without cellular reaction, and gliosis of the cerebral white matter and the brain stem of focal as well as diffuse type. The CNS changes were of hypoxic type and might have been caused at delivery or shortly after delivery. They seem too insignificant to have caused the collapse, but could have been an auxiliary factor. It cannot be determined whether the bronchopneumonia caused the collapse or if it developed as a consequence of the unconsciousness. Interestingly, no other pathological changes of significance were found.