Description: One of the most fundamental information needs to support ecosystem assessment and land management planning is consistent, continuous, and up to date vegetation data of sufficient accuracy and precision. The Northern Region Existing Vegetation Mapping Program (VMap) database and map products help meet this information need and provides the Northern Region with a geospatial database of existing vegetation produced using consistent analytical methodology according to the Existing Vegetation Classification and Mapping Technical Guide (Brohman and Bryant, 2005) to support the Region 1 Multi-level Classification, Mapping, Inventory, and Analysis System, R1-CMIA (Berglund et. al., 2009). The Bitterroot and Lolo National Forests (BitLo) VMap database provides four primary map products; lifeform, tree canopy cover class, tree size class, and tree dominance type to support mid and base-level analysis and planning. VMap uses the Region 1 Existing Vegetation Classification System (R1-ExVeg) (Barber, et.al. 2009) in its map unit design. The R1-ExVeg system describes the logic for grouping entities by similarities in their floristic characteristics. This has been an iterative process in Region 1 as different classification schemes have been tested and evaluated for utmost utility by end users. The system was designed to allow consistent applications between Regional inventory and map products within the R1-CMIA framework. VMap is a remote sensing derived product. As such, it uses a combination of high resolution airborne imagery and a nationally available digital elevation model (DEM). The image data, acquired in 2013 (i.e., pixels) are put through a process of aggregation to derive spatially cohesive units (i.e., polygons). A small portion of these polygons are then sampled in the field to determine their composition and through spatial statistics, un-sampled polygons are given labels based on an analysis of the sampled polygons. Draft map products are then reviewed and appropriate changes are made in the labeling algorithms. Final results are then used to populate the VMap database.An accuracy assessment was conducted to provide a validation of the data, giving an indication of reliability of the map products, so that managers are fully informed throughout the decision making process. Estimates of overall map accuracy and confidence of individual map classes can be inferred from the accuracy assessment error matrix derived from the comparison of known reference sites to mapped data. These accuracy assessment results are relevant to the entire BitLo as a whole ranging from 60-90%, depending on the attribute in question.