This paper describes LaoGEM (Lao General Equilibrium Model), a 20 sector, 400 household general equilibrium model of the Lao economy, constructed specifically for the analysis of the effect of road improvement on rural poverty incidence in Laos. Unless otherwise stated, the database of the model refers to the year 2002. These features are relatively standard for comparative static general equilibrium models, except for the treatment of the household sector. Three features are important. First, the model distinguishes four categories of households, one urban and three rural, the latter differentiated by the quality of roads which service the villages in which these rural households are located. Second, each of these four categories of households contains 100 household sub-categories, arranged by real expenditures per household member. Third, the three rural household categories differ according to the transport costs that they face, commensurate with the quality of roads servicing them, and using information on transport costs.