Yes, Condesa is a safe neighborhood in Mexico City. In fact, it's one of the safest areas in the city. In general, you can walk around here at night without any problem. However, as with any big city, it's still a good idea to take some basic precautions to prevent yourself from becoming a victim of crime. These precautions include: not walking down the street with your phone in your hand, being especially careful if wearing noise-canceling headphones, not leaving your drinks unattended in bars, and avoiding walking home by yourself at night if you're intoxicated.