I about to start a 4 month back packing trip around South East Asia, I will list the areas below. One major concern for me is avoiding coming into contact with the sex industry and the tourists who come to seek it. I have heard that it is a very large industry in Southern Thailand and so have decided to avoid this area. But I have heard that it is very far spread, Cambodia , northern Thailand to some degree.
While most countries of Southeast Asia resist the classification of prostitution as an industry, or sex work as an acceptable occupation in national statistics, there is no doubt that millions of women in the region earn a livelihood from selling sexual services. To do this virtually all of these women are forced to leave their birthplaces and residences and migrate to places where they will have some anonymity. Often this migration is involuntary, and sometimes it involves cruel exploitation. This paper pulls together the limited data available to gain insights into the shadowy world of Asian prostitution. It concludes that while governments frequently crack down on women selling sex, they ignore the roles of male customers, and often protect the criminal elements who use kidnapping and violence to exploit the women. There is a need for legalization of the sex industry to protect women and expel criminals.
The legality of prostitution in Asia varies by country. In Asia, the main characteristic of the region is the significant discrepancy between the prostitution laws which exist on the books and what occurs in practice. For example, in Thailand prostitution is illegal,  but in practice it is tolerated, and the country is a destination for sex tourism.
Security threats are no longer just about military confrontation, territorial disputes, and nuclear proliferation. They also arise from nonmilitary dangers such as climate change, natural disasters, infectious diseases, and transnational crimes. Among these nontraditional security threats, human trafficking looms large, especially in Southeast Asia, where natural disasters and military conflicts lead to displaced people and refugees, who are particularly vulnerable to this heinous crime. In Southeast Asia and elsewhere, nontraditional security threats have two defining features: they are transnational and complex.