The presence of the characteristic early glomerular hyperfiltration seenin diabetes was originally suggested long ago by Cambier (1), indeed a few years before the well-known studies by Kimmelstiel and Wilson (2) that documented the typical glomerular structural lesions in diabetic patients. Brenner (3,4), in his breakthrough glomerular hyperfiltration- hemodynamic theory, also used diabetes as an example and proposed that hyperfiltration was an important factor in the genesis of glomerular damage, and not only in the damage caused by diabetes. This means that the two classic findings (1,2) may well be closely connected, with the former causing the latter.