A variety of dietary and metabolic factors may contribute or cause stone formation in idiopathic calcium oxalate nephrolithiasis. Dietary factors include a high intake of animal proteins, oxalate and sodium, and a low intake of fluids and potassium-containing citrus products. Some of the metabolic causes of stones are hypercalciuria, hypocitraturia, gouty diathesis, hyperoxaluria, and hyperuricosuria. Dietary modification, to be applied in all patients with stones includes a high fluid intake, restriction of oxalate and sodium, and balanced diet with animal proteins complemented by adequate intake of fruits and vegetables. When dietary modification is ineffective in controlling stone formation or in the presence of severe metabolic derangements, a pharmacologic intervention may be necessary. In a simple approach, thiazide or indapamide with potassium citrate is recommended for patients with hypercalciuria, and potassium citrate alone for the remaining normocalciuric subjects.