We have read the letter from Dr. Slotkowski with interest and we agree with him upon the need for a uniform terminology. The reason for our use of the term vaccinia gangrenosa was that it emphasized the clinical picture and had an historical background, albeit a somewhat tenuous one. The main reason for having a separate term for this type of complication is that we would suppose that it is only in such cases that the use of hyperimmune gamma globulin should be used.