Given continual shifts in the patterns of
internal migration in both developing and more
developed parts of the world, and the impor
tance of these processes for social, political, and
demographic conditions, mobility between geo
graphical areas within countries will continue to
garner a good deal of research interest. Ideally,
data from censuses and surveys will be supple
mented by new sources that provide the basis
for more effective cross national comparisons
of migration behaviors, the direct assessment of
multifaceted motivations for migration, and the
opportunity to explore how the composition of
social networks, social structural conditions, and
other factors alter internal migration behaviors.
SEE ALSO: Demographic Data: Censuses,
Registers, Surveys; Environment and Urbani
zation; Metropolis; Migration: International;
Migration and the Labor Force; Residential
Segregation; Suburbs; Sunbelt; Uneven Devel
opment; UrbanRural Population Movements
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Mary M. Kritz
International migration is generally defined as
the change of a persons usual place of resi
dence from one country to another. The Uni
ted Nations recommends that a time element of
at least one year be added to this definition in
order to differentiate international migrants
from international visitors. Because interna
tional migration is a dyadic process, this defini
tion applies both to moves into and out of a
given country and the process can be examined
from the standpoint of the sending or receiv
ing country. Arrivals and departures of citizens
and foreigners are part of the international
migration process, which has four components:
(1) the in migration of persons to a country
other than that of their place of birth or citizen
ship; (2) the return migration of nationals to
their home country after residing abroad;
(3) the out migration of nationals from their
home country; and (4) the out migration of for
eigners from the foreign country to which they
migrated. The first component, commonly
referred to as immigration, has received the most
research and policy attention.
MIGRATION AND THE NATION STATE
International migration is an appendage of the
nation state era. Throughout history, people
have migrated or left their communities and
homelands and established residence else
where. Only after the worlds territory became
organized into states with internationally recog
nized boundaries did the distinction between
internal and international migrants emerge.