Abstract. Plant functional types are a necessary device for reducing the complex and often uncharted characteristics of species diversity in function and structure when attempting to project the nature and function of species assemblages into future environments. A workshop was held to review the current methods commonly used for defining plant functional types, either globally or for particular biomes, and to compare them with the field experiences of specialists for specific biomes of the world. The methods fall into either an objective and inductive approach or a subjective and deductive approach. When the different methods were tested, it was generally found that the classification for one site or environment was not wholly applicable to a different site or environment. However, the degree of change which is necessary for adjustment between environments may not prove to be a major limitation in the use of functional types.