This handbook describes the Long Term Resource Monitoring Program (LTRMP) General Wetland Vegetation Classification System developed as part of a multi-state and Federal partnership for the Upper Mississippi River System. This classification system consists of 31 general classes and has been used to create systemic land cover/land use maps throughout this diverse river system. In addition, it describes the evolution of the General Wetland Vegetation Classification System, discusses the process of creating a map, and describes each of the 31 general classes in detail. This handbook also acts as a pictorial guide to illustrate each of the general classes as they may appear in the field, as well as on color-infrared aerial photographs.