The aim of the thesis is to investigate patterns and consequences of internal and international migration in Laos during the period 1985-2005 on both a macro-and a micro-level. The thesis focuses on the influences of socio-economic change and government policies on inter-regional and rural-urban migration as well as on crossborder migration from Laos to Thailand. The study also examines the effects of migration and industrial factory work on gender relations during economic transition and consequences of undocumented migration to Thailand. The background consists of a discussion on socio-economic change within the country and on government policies influencing migration patterns, as well as on how socio-economic change, urbanization and industrialization in the region affect internal and international migration in Laos. The thesis consists of three empirical studies which derive from different sources of data; the first is based on Population Censuses in 1995 and 2005 and the second and the third draw from empirical surveys in 2004-2005 and 2006. Paper I focuses on how socioeconomic factors and government policies influence migration patterns in Laos. The paper found that the interregional migration rate decreased in the later census period. This was due to significantly higher rural-rural migration in the earlier period, which in turn was influenced by various types of government policies. Papers II and III are based on micro surveys; paper II focuses on an urban industrial area in Vientiane Capital and explores the current feminization of rural-urban migrations during economic transition with specific focus on the effects of industrial work on gender roles and status of women as industrial workers. Industrial work was seen by the women as temporary jobs for saving money, for sending remittances, and for either returning home or moving to other jobs in Vientiane or Thailand. Paper III is based on surveys in three provinces, and deals with undocumented migration from Laos to Thailand and its consequences. Different income levels, existing social networks, similar language and socio-cultural backgrounds were determinants of cross-border migrations. The study found that migrants who had contacts with informal brokers were highly exposed to risks of human trafficking and violence.