This paper discusses the issues that arise during the development of a land use database for TRANUS, an integrated land use and transportation model. The paper addresses the methodologies used to develop the necessary databases for a state-wide land use and transportation model currently under development for the Oregon Department of Transportation by Parsons Brinckerhoff. The paper will discuss the issues of data availability, data integration between different data sources to estimate required individual data variables, alternate methodologies for calculating variables needed by the model, the statistical assessment of the available data, and solutions to data problems (e.g., outliers, missing data, etc.) Oregon's state-wide model uses data derived from land sales records, county assessor records, census data, GIS data, and state mandated employment data (ES202). TRANUS requires an estimate of land cost per square foot for different economic sectors in order to model the consumption of land by competing uses. Alternative methodologies for estimating missing data from available data sources will be discussed. The model contains 122 transportation analysis zones, which are based on census tracts. This structure facilitates the tracking of land use and demographic data over time. The strengths and weakness of the census tract based system zone system will also be discussed.