Ok so there are like a million taxis in this city...no really. I'd say that 98 per cent of them are totally safe. That leaves about 20,000 not so safe cabs around. Really it all depends on the money you are willing to spend/lose. There are taxi cab companies, TaxiMex for example, that you can even get a receipt for tax purposes after you pay with your credit card, that are honestly not that expensive by first world standards. I took one such cab half way across the city one night (about a 35 minute drive, no traffic) and it cost about 80 pesos. This is cheaper than a cab off the street late at night...which is the dangerous time. I have done that as well, and I have also refused cabs after a quick glance inside. There should ALWAYS be a taxi meter. It is always better if it is in use say "Taximetro" and if he nods his head it's gonna be a good deal. Other things. Don't get a ratty looking cab. Make sure to check that there is the cab drivers id clearly posted, and that the guys face is the same as the guy driving the care. If for whatever reason, your intuition is telling you something is wrong on the ride. DON'T PANIC. Calmly tell the man "Aqui, esta bien" and he should pull over right then and let you out. You can get another cab. Taxi stand cabs (Sitio) are generally safe, reliable, and only a bit more expensive. I use cabs whenever I can afford them. At night they are the fastest and sometimes only way to get around town. The Metro closes early. 12 midnight.