Pollen and spores are ubiquitous, and preserve exceptionally well. This, and their enormous structural diversity, offers exceptional opportunities for integrating findings from studies of both recent and fossil material, and for developing new insights into the pathways and processes of diversification. This volume brings together both international authorities and younger researchers who have developed novel approaches from such diverse fields as paleobotany, ontogeny, molecular biology, and systematics. Three main issues are discussed: the evidence provided by the fossil record, the contribution of ontogenetic data, and the methods of systematic analysis. Of special interest are the sections detailing the most recent findings regarding fossil angiosperms and ontogeny in primitive angiosperms. The information provided will be of great interest and relevance to such disparate disciplines as vegetational history, geology, plant taxonomy and plant evolution.