The Tompkins County Planning Department utilized inter-departmental mapping expertise of the Tompkins County Information Technology Services GIS Division to produce a land use and land cover data set of Tompkins County, NY. The need for this data set has been identified by various county departments, local municipal agencies, and other not-for-profit organizations. Traditionally, land use and land cover maps have been developed by interpreting aerial photographs, delineating land use and land cover polygons onto a geo-referenced base map, and then digitizing the line work. This project uses an innovative methodology to develop a land use and land cover map entirely within a digital environment. Digital Orthophoto Quarter Quadrangles (DOQQ), a type of color infra-red digital aerial photograph, and a number of other secondary digital data sources (wetlands, hydrology, and planimetric base data) are being used to interpret and delineate land use and land cover directly on-screen. This technique is more time efficient by reducing the number of processing steps required, as well as more accurate by reducing cumulative errors introduced through multiple processing steps. A land use and land cover classification system was designed to meet the needs of the users of these data. A needs assessment meeting was held prior to the project to determine the needs of planners, local municipalities, advisory boards and educators. In 1968, the Land Use and Natural Resource Inventory (LUNR) a state-wide land use and land cover mapping project, used aerial photographs to identify 130 land use and land cover classes. The Tompkins County land use and land cover classification system has been designed to be comparable with the LUNR classification system. Comparable classification systems will enable users to analyze changes in land use and land cover over the previous thirty year time period Provides a county-wide data set of all tax map boundaries for the tax parcel maps in Tompkins County. Potential uses of these data include land use and land cover time change analysis, comprehensive planning and development suitability analysis.