This article lays out three overarching dimensions of current theoretical models of migration flows: a “spatial” dimension, which describes pushes and pulls in origin and destination countries; a “temporal” dimension, which explains why migration streams begin and either grow or dissipate; and a “volitional” dimension, which explains at the individual level how migrants respond to these forces and to the changing context in which migration occurs. The spatial dimension includes the four primary models of migration, based on neoclassical economics, world systems theory, the new economics of...

This article lays out three overarching dimensions of current theoretical models of migration flows: a “spatial” dimension, which describes pushes and pulls in origin and destination countries; a “temporal” dimension, which explains why migration streams begin and either grow or dissipate; and a “volitional” dimension, which explains at the individual level how migrants respond to these forces and to the changing context in which migration occurs. The spatial dimension includes the four primary models of migration, based on neoclassical economics, world systems theory, the new economics of labor migration, and social capital theory. By placing these demographic-economic approaches into a synthetic, three-dimensional framework, the article addresses the discrete causes of migration while bridging the artificial (often disciplinary) divide among competing explanations.