This special issue of Palynology honors the memory of John H. Wrenn. Each contributed paper has been written by at least one author who regarded John as a colleague or friend. It is singularly fitting that AASP–The Palynological Society’s own journal should publish this collection of papers, as John was deeply committed to the American Association of Stratigraphic Palynologists (AASP, the previous name of our society) for much of his professional life. John’s involvement with AASP began in 1986 when he organized and chaired the First Symposium on Neogene Dinoflagellate Cyst Biostratigraphy during AASP’s 20th Annual Meeting in New York City. This was an inspired initiative as it launched the study of Neogene dinoflagellate cysts into the mainstream of palynological research. The accompanying proceedings (Wrenn et al., 1986), which were made available at the meeting, revealed a hitherto unappreciated level of taxonomic diversity for this time interval. During this same year, John took over the editorship of the AASP Newsletter (1986–1988), and in doing so began a life-long commitment to editing that included Palynos (the newsletter of the International Federation of Palynological Societies) from 1992 to 1996, and several books (Head and Wrenn, 1992a; Bryant and Wrenn, 1998; Wrenn et al., 1999) and conference proceedings. In addition to serving on numerous AASP committees, he was its President from 1991 to 1992, and in 1993 was appointed as the inaugural Director of the AASP Center of Excellence in Palynology which had been established at Louisiana State University (LSU) in Baton Rouge. It was testimony to John’s modesty that he soon had the name changed to Center for Excellence in Palynology, believing that the original name was presumptuous. His many contributions to this association were recognized in 1998, when AASP’s Distinguished Service Award was conferred upon him. John’s research interests …