Health and Safety
It's a good idea to avoid tap water, as pipes in many older buildings are made of lead. Almost everyone drinks locally bottled agua mineral (mineral water), which is available con gas or sin gas (with or without carbonation).
Uruguay would win most "Safest South American Country" competitions, but standard travel precautions apply. Keep an eye on your purse or wallet, avoid unnecessary displays of wealth, and avoid wandering back streets of Montevideo at night.