The movement of labour from one location to another in Pakistan has increased in recent years. This article begins by reviewing the previous literature pertinent to labour migration within Pakistan. Next, a migration equation at the aggregate level is specified, based on the expected socio-economic determinants of labour migration and data availability. Regression analysis was used to identify and quantify the determinants of interdistrict migration in Pakistan during the period 1971–1980. The results demonstrate that one of the major determinants of migration into a district was the percent of previous migrants in a district's population. Interdistrict migration was also significantly associated with the socio-economic variables of urbanization, population density, and literacy rates. The research presented here provides evidence that the movement of labour between districts in Pakistan is towards locations of superior socio-economic conditions. Migration was found to become more responsive to urbanization, population density, and literacy rates over time, and less responsive to previous migration over time. Given the huge increase in productivity in the agricultural sector brought about by the Green Revolution, the movement of workers out of agricultural areas and into industrial areas is expected to continue into the future. This rural-to-urban flow may be limited by the level of population density; crowded living conditions were found to be negatively associated with labour migration.