Cross-border crime is seen as a serious challenge in most countries, and therefore adequate measures should be put in place by the governments of the affected countries to contain these international security problems from becoming worse. Human trafficking, weapons smuggling and money laundering are among some of the activities engaged in by terrorists to raise funds around Southeast Asia. In addition, human trafficking also contributes to the funding of terrorist related activities that are currently perpetuated in the Philippines. The right method implemented in the deradicalization program related to cross-border terrorism is discussed in this chapter. Secondary data was collected for the purpose of this research through literature review and observation from various sources such as news, online news, and other trusted sources. Findings from this chapter have proved that targeting of strategic locations has played a significant role in contributing to cross-border crime activities as well as rehabilitation programs done by SEA countries. Success stories from Malaysia and Singapore can be applied to others as part of long-term initiatives to create stability and peace in this region.