<mark>influence migration decisions and outcomes. To shed light on the drivers of work migration, we further exploit the time dimension of these data by using lagged explanatory variables that precede the migration event. Second, the paper relies on a robust panel tracking exercise to contribute to the growing literature on the causal impact of internal migration on welfare. We rely on exogenous variation in the intensity of conflict, rainfall shocks for the main staple crop, distance from the capital city, and ethnic migrant networks in urban areas to explain migration decisions and estimate their welfare impact. Given the importance of rural-urban migration for the structural transformation of Uganda’s economy, we also estimate the added marginal impact of moving to an urban area and compare it to that of moving to a rural area.</mark> Drawing on a rich set of nationally-representative panel data, we find that migrants experience a 58 percentage point gain in per capita consumption after moving. Moving to an urban area, meanwhile, generates even larger returns: urban migrants enjoy a 65 percentage-point increase in per capita consumption growth versus a 56 percentage-point increase in per capita consumption growth for rural migrants during the 2005-2010 period. Despite these potential gains from urban migration, the bulk of Uganda’s migration flows still occur _within_ rural areas. Several key drivers of these moves emerge from the analysis. Among young adults, rainfall shocks on maize production spur an exit from agriculture in favor of urban areas. Meanwhile, living in a remote area constrains individuals from affording the long and costly move to urban areas, leading them to migrate to closer rural destinations. The intensity of violent conflict and thin ethnic migrant networks in urban areas are further found to facilitate rural migration. Being a child of the household head, irrespective of gender, and being a more educated individual is associated with a higher propensity to migrate. Policies to capture the welfare improvement from rural-urban migration should thus address the development of road infrastructure and urbanization, as well investments in the education of male and female children in rural areas.

The remainder of this paper is structured as follows. Section II assesses the contributions from the theoretical and empirical literatures on migration. In Section III, we provide a description of the panel data being used for the descriptive analysis and an overview of the tracking survey data. Section IV uses the full panel data set to identify the drivers of household-level work migration choices in Uganda. In Section V, we exploit a tracking panel survey to identify the causal impact of migration on welfare. We provide a set of conclusions in Section VI.

# **II. Literature**

<mark>Early theoretical contributions on migration focused on economic mobility as a one-way and one-off move from rural to urban sectors to increase wages, while modern theories have placed an emphasis on strategic household decisions to send a migrant, the reliance on kinships and networks, and the links between migrants and their families through remittances.</mark> <mark>The classical model for labor migration proposed by Lewis (1954), as well that of Harris and Todaro (1970), attempted to characterize the effects of migration from the rural to urban sectors. According to the Lewis (1954) model, labor surpluses in the rural sector can be reallocated to the urban sector through the ruralurban migration of workers and reduced rural unemployment. Labor migration thus serves to increase the marginal productivity of labor-intensive technologies in the urban sector and contributes to capital accumulation and economic growth. While Lewis’ model and extensions find rural-urban migration beneficial, Harris and Todaro instead critique the argument that the urban sector can exploit an unlimited supply of excess rural labor. According to their model, as long as wage differentials are favorable in the urban sector, rural-urban migration flows will continue and can lead to an increased unemployment rate</mark> 3