This paper uses China's 1990 Census 1% microdata and studies interprovincial migration with reference to a core Chinese socioeconomic institution, the household registration (hukou) system. We ยฎrst compared the socioeconomic characteristics and geographical patterns of long-distance hukou and non-hukou migratory ยฏows, and developed a framework of dual migration circuits. With this framework, we used a statistical model to evaluate migration rates in relation to both origin and destination variables. It was found that these two types of migrants shared some general demographic characteristics, but displayed substantial socioeconomic differences. Hukou migrants tended to originate in urban areas, had an extremely high share of the college-educated and were employed in more skilled jobs, while non-hukou migrants were mostly from rural areas with much lower education attainment. Hukou labour migrants tended to move through government and formal channels, while non-hukou migrants relied on their own, often informal, sources for jobs. We used a set of place-to-place migration models to assess the differential effect of the same variables on different types of migration. While hukou and non-hukou migration (including rural labour migration) were, as expected, deterred by distance and moved mostly to more economically developed coastal provinces, the