Koh Samui, like all of Thailand, is considered quite safe for travellers and expats alike. As violent crimes are rare against foreigners, it is advised to take normal precautions just as you would in your home country. Statistically, Koh Samui and Thailand have less overall crime rates than that of most Western countries. Petty crimes can and do happen, although it is not prevalent. Taking a stroll after dark is always not recommended, regardless of what country in which you reside.