The large arteries in the leg were examined at angiography in 47 insulin dependent diabetics. Arterial lumen size and the short- and long-range variation as well as intima and linear media calcifications were evaluated quantitatively. Significant correlations were obtained between the duration of diabetes on the one hand and media calcification and uniform narrowing of femoral, crural and foot arteries, as well as increased short-range lumen variation on the other hand. Statistically, the narrowing of the femoral artery and the increased short-range, small-scale variation of its lumen were closely related, whereas media calcifications per se appeared unrelated to the lumen size, locally as well as globally. A high degree of concordance was found among the femoral, crural and foot arteries with respect to both the presence of linear media calcifications and their severity. Spotty intima calcifications were clearly associated with irregular arterial narrowing, but were dependent on age and not on the duration of diabetes. It is suggested that the uniform media calcification, narrowing of the arteries and short-range, small-scale variations of the lumina are expressions of a specific diabetic macroangiopathy.