The cause of urinary stone disease can now be detected in approximatel
y 80% of patients. Effective treatment can substantially reduce the re
currence of urinary calculi. Proper therapy depends on a thorough unde
rstanding of the physiology of calcium, oxalate, uric acid, cystine, a
nd struvite formation and the medication developed for prevention. Thi
s article reviews the physiologic basis of urinary stone management in
a straightforward, understandable fashion.