War-torn countries have become havens and recruiting grounds for international terrorist networks, organized crime, and drug traffickers, and tens of millions of refugees have spilled across borders, creating new tensions in host communities. Ethnicity, adverse economic conditions, low levels of international trade and conflict in neighboring countries are all significantly correlated as well. As the global population continues to rise, and the demand for resources continues to grow, there is significant potential for conflicts over natural resources to intensify. The potential consequences of climate change for water availability, food security, the prevalence of disease, coastal boundaries, and population distribution are also increasingly seen as threats to international security, aggravating existing tensions and potentially generating new conflicts. Research and field observation indicate that natural resources and the environment contribute to the outbreak of conflict in many main ways. Economic incentives related to the presence of valuable natural resources can hinder the resolution of conflict and complicate peace efforts.