PURPOSE: In this systematic review we summarize information on animal models of stone formation, the similarities of stone formation between humans and nonhuman animals, and the management of naturally occurring stones in animals, particularly dogs and cats. MATERIALS AND METHODS: A comprehensive review of the peer reviewed literature was performed using the key words urolithiasis and animals. The search was then limited to articles in English that were published within the last 30 years (1977 to 2007). RESULTS: Multiple animal species are affected by urolithiasis and the mechanisms of formation appear to mirror those in humans. Recently described models of animal stone disease may help us better understand and ultimately treat nephrolithiasis in humans. CONCLUSIONS: The pathogenesis of urolithiasis and treatment protocols in animals parallel those of humans. Given the number of similarities between treatment patterns for humans and animals, many urologists are now being integrated into the treatment of animals.