The relation of salt to hypertension and kidney disease had been well known at the turn of the last century, but the importance of salt has been grossly neglected more recently. There is a close link between salt intake and hypertension, as well as partially blood pressure-independent target organ damage including renal disease. In the general population, high salt intake is associated with hypertension and cardiovascular events. Salt loading also increases albuminuria in individuals without primary renal disease and raises excretion of albumin and protein in patients with renal disease. It aggravates proteinuria and glomerulosclerosis and accelerates progression in most animal models of renal damage. The effect of salt restriction cannot be reproduced by treatment with diuretics. Inappropriate increase of intrarenal angiotensin II and increased reactive oxygen species are the major culprits responsible for salt-related renal damage.