“The path of carbon in photosynthesis”for Progress in Botany: 50 years of Calvin-Benson cycle – 30 years of Kelly-Latzko reviews While writing this Foreword and trying to focus my thoughts on the bioch- istry of photosynthesis, a handsome slim hardcover booklet of 104 pages bound in dark blue linen is in front of me on my desk: “The Path of Carbon in Photosynthesis” J. A. Bassham and M. Calvin,1957 I acquired it in the month of my oral Ph. D. -exams,April 1960,to get prepared with the Nobel-laureate’s text. In 2004 in his last swan-song review for Progress in Botany Grahame J. Kelly celebrated “The Calvin cycle’s golden jubilee”in an overview of 50 years of carbon flowing for the progress in botany. He had met Erwin Latzko in 1970 in another then foremost and now historic place of the biochemistry of photosynthesis, the laboratory of Martin Gibbs at Brandeis University, Massachusetts. Four years later Latzko and Kelly (1974) published their first joint review on photosynthetic carbon metabolism,starting off a long flow of articles on the flow of carbon in the series Progress in Botany. Most faithfully they produced regular accounts of the progress in Progress in Botany every second year, and when Erwin Latzko decided to retire after the 1996 review Grahame Kelly carried on alone.