The National Park Service (NPS) Vegetation Inventory Program (VIP) is an effort to classify, describe and map existing vegetation of national park units for the NPS Nature Resource Inventory and Monitoring Program. The Washington Natural Heritage Program (WNHP), working in cooperation with the North Coast and Cascades Network (NCCN), has completed a vegetation classification and map of San Juan Island National Historical Park (SAJH). Every vegetation type with the park was classified and mapped to at least the NVC Alliance level. Many types were classified and mapped to the Association level of the NVC.