Trafficking in persons, the primary objective of which is to gain profit through the exploitation of human beings, is prohibited by the Protocol to Prevent, Suppress and Punish Trafficking in Persons, Especially Women and Children; it is also criminalized in the national legislation of a growing number of States. Trafficking is a severe violation of the human rights of its victims. It is often conducted across borders, sometimes over great distances, although certain countries have a significant problem of in-country human trafficking.
The Protocol against the Smuggling of Migrants by Land, Sea and Air criminalizes the facilitation of illegal entry, or enabling the stay of people who are not nationals or permanent residents of a State for the purposes of obtaining a financial or other benefit; it therefore targets the criminals who smuggle migrants and not the migrants themselves. The smugglers may provide different kinds of assistance for financial or material benefit, ranging from forged documents to transportation, and show variation in their level of organization. As destination countries have increased control over their borders to prevent irregular migration, and in many regions of the world also in the context of a lack of adequate legal channels for entry, more people, including refugees and others in need of international protection turn to organized criminal groups in order to arrange their travel and entry. Official counter-smuggling measures may themselves expose migrants to human rights violations, by State and non-State actors. Smuggled migrants are frequently abused or exposed to dangerous and even life-threatening conditions. It is estimated that there are 50 million migrants without the necessary documentation in the world today and that a significant portion of these persons paid for help in crossing borders illegally. The profits generated by people smuggling fuel corruption and strengthen organized crime.
There are a number of legal and practical interlinkages between human trafficking and the smuggling of migrants. Trafficked persons are often smuggled across borders and smuggled migrants are particularly vulnerable to being trafficked given their precarious situation. It can be difficult to determine whether a person is being smuggled or trafficked. Practitioners need to be aware of the distinct features of both crimes. Responses to both should include prevention; prosecution; and the protection of trafficking victims and the human rights of smuggled migrants.
Smuggled and/or trafficked persons can be in need of international protection and qualify for refugee status. For people who are forced to flee resorting to human traffickers or smugglers may be the only possibility to reach safety. Refugees may also become a target of human trafficking if they live in precarious situations in their country of asylum. In addition, given that severe forms of exploitation and abuse are inherent in the trafficking experience, the victim may not be able to return home without serious risks. Trafficking may give rise to a well-founded fear of persecution and a claim for refugee protection. It is therefore important in such cases that trafficked and smuggled persons are referred to the asylum procedure where such claims can be properly assessed and addressed.
Given the seriousness of the threats that these crimes represent to individuals and to communities, the international community has responded, seeking to prevent and combat human trafficking and migrant smuggling. Much has been done and many lessons can now be learned as to what progress has been made, what has been effective and what areas continue to pose challenges.
 UNDP, Human Development Report 2009; Overcoming Barriers: Human Mobility and Development, New York, 2009; UNODC, The Globalization of Crime: A Transnational Organized Crime Threat Assessment, Vienna, 2010.