Describes a method for developing a general-purpose ecological model of community types and successional relationships within a forest habitat type (potential vegetation). This model is based upon data collected from a large number of seral stands, and it is intended for use in land management and planning. The successional model has a framework of structural stages subdivided into community types based on overstory and undergrowth composition. The usual pathways or directions of succession between community types are identified. To aid prediction of vegetational development after different treatments, the model shows apparent relationships among posttreatment vegetation and the original vegetation, site characteristics, and kind of treatment. This method was used in developing successional classifications (models) of four major forest habitat types in western Montana.