Migration is a complex human and social phenomenon, which has been a source of prosperity and innovation throughout the history of humankind. Migration, whether regular or irregular, is not per se a crisis or a problem and should not be confused with the smuggling of migrants, which is criminal conduct that can occur in the context of migration. This section will address the issue of migration to better understand the broader context in which such criminal conduct develops.
Migration has always occurred, though certain events have precipitated large increases in the movement of people. For example, during the twentieth century, the Great Depression, the World Wars and decolonization all caused major cross-border displacement. According to the the UN Refugee Agency, the United Nations High Commissioner for Refugees (UNHCR), the world is currently witnessing some of the largest migratory movements on record. At the end of 2016, approximately 65.6 million people had fled their homes due to conflict and persecution (often referred to as 'involuntary migration'). Many people are also compelled to leave their countries of origin due to, inter alia, natural disasters, economic crises or the desire to reunite with family members in other countries.
Migration is driven by so-called push and pull factors, which push people to migrate from their countries of origin and attract them to certain destinations. Migrants are often motivated to move by a combination of several of these factors. Indeed, push and pull factors are commonly interconnected, giving rise to complex causes for migration.
To comprehensively understand the phenomenon of migration, it is important to also consider factors that prevent individuals, who otherwise wish to migrate, from doing so. These factors often centre on restrictive migration policies (especially in destination countries), the lack of regular avenues for migration and the inability (or ability) of individuals to circumvent the barriers erected by countries to control and regulate international movement. Professor Jorgen Carling refers to ' involuntary immobility' to express this reality, which influences migratory movements around the world.
The displacement of large numbers of individuals, especially in the context of mass migration, has consequences (see Box 3 below). These consequences do not exist in isolation and are often interrelated.
Consequences of migratory flows
Nonetheless, it is important to underline that migration has been an integral, and generally positive, part of the history of humanity. It generates important benefits for both countries of origin and destination, as well as migrants and their families. Concerns may arise, however, when circumstances are not suited to the consequences of migration flows; for example, when the policies or material capabilities of destination countries do not suitably accommodate the number of individuals intending to enter and/or stay in the country.
Migrant smuggling develops in the context of migratory aspirations and conditions, together with States' rules on the entry, transit and stay of migrants. States' migration policies are often restrictive, reflecting the limited ability of countries to absorb very large numbers of migrants in short periods of time and the preference of States for certain types of migrants (usually high-skilled migrants). Many individuals wishing to migrate do not satisfy these legal requirements or are otherwise unaware of them. Nonetheless, strict migration policies - including restrictive asylum policies, severe penalties for irregular entry and the enforcement of border controls - have been largely ineffective in decreasing migratory movements. By limiting avenues for regular migration, restrictive policies have instead led to an increase in demand for the services of individuals (smugglers) who assist migrants in evading migration controls and enable them to irregularly enter and stay in destination countries (see, for example, Taran, 2003). Such measures have also led to the growing professionalization of smugglers. Illegal services are set up to respond to the demand of individuals who wish to migrate to improve their lives or for other compelling reasons, but who cannot migrate legally. Smuggling of migrants is often the last resort for many individuals trying to escape war, violence, and poverty (see proposed Activity 1 under ' Additional exercises').
By way of example, Europe has been a significant destination for migration for many years, but from 2015 onwards the EU registered record levels of irregular migration. The reasons for this increase relate to a complex set of factors stemming from political upheaval in the Middle East, Africa and South Asia. Broadly speaking, the number of irregular migrants detected in the EU began to increase in 2011 following the Arab Spring and the collapse of the Qaddafi regime in Libya. Sub-Saharan Africans who had previously migrated to Libya began to enter Europe to flee unrest in the post-Qaddafi era. The International Organization for Migration (IOM) estimates that more than 464,000 migrants crossed into Europe by sea in the first nine months of 2015 ( IOM, 2018). Syrians, Afghans and Eritreans represented the largest groups of migrants. Deteriorating security and growing poverty in Iraq, Nigeria, Pakistan, Somalia and South Sudan have also contributed to the migration flows towards Europe. Due to its geographic location, the EU has become a predominant destination for migrants leaving these countries. Even migrants wishing to migrate to North America regularly transit through European countries. The pressure to leave countries of origin, combined with economic difficulties and the inability to meet requirements for regular entry into the European Union, led to a substantial increase in the use of smuggling services.
It is also interesting to note that migration routes evolved - and do evolve - dynamically, influenced by the situation in countries of origin and restrictive border management policies in countries of transit and destination. Smugglers adapt to actions and new policies by law enforcement, thus finding alternatives that offer more probability of success and profitability.
For an overview of global flows and patterns of smuggling of migrants, see the UNODC Global Study on Smuggling of Migrants, published in 2018. For a general idea of global flows of migrants, refugees flows between and within regions, and asylum applications in 2015, see the interactive map Global Migrants, Refugees & Asylum Applicants . See proposed Activity 3 under ' Additional exercises'.