Phuket is not a particularly unsafe place for tourists, but it is smart to follow the same safety advice you would when at home if you’re out and about at night. Try and stay in a group, don’t go anywhere you aren’t familiar with, and try not to end up on any unlit streets or alleyways. Women in particular should also keep a close eye on their drinks when they are out in the evenings, in case someone tries to spike them.