There were incidences of 0.7% severe and 5.5% mild complications in 1,971 direct puncture carotid angiograms done over a 5-year period. In 1,035 retrograde branchial angiograms, there was a 0.6% incidence of severe, and a 4.7% incidence of mild, complications. Complications tended to increase with increasing age of the patient. Brachial angiography is virtually free of life-threatening complications, and the incidence of neurological sequelae was markedly less than that shown by a comparable analysis of catheter angiography. Of patients undergoing 1,542 fractional pneumoencephalograms, 2 had severe complications.