This volume contains the main lectures and poster contributions presented at the 7th International Symposium on the Plant Hormone Ethylene held in Pisa (Italy), June 18-22, 2006. This international scientific event was organized by the University of Padova and the Scuola Superiore Sant'Anna of Pisa and took place on the premises of the Scuola Superiore Sant'Anna. We would like to thank the Ministry of Agriculture and Forestry, the Ministry of University and Scientific Research of Italy, the University of Padova and the Scuola Superiore Sant'Anna of Pisa for partially funding this symposium. Appreciation is also extended to a number of local insti- tions that generously contributed to the success of this important event. We are indebted to the members of the scientific committee. A special appreciation goes to the local organizing committee headed by Prof. Giovanni Serra. Finally, we gratefully acknowledge Dr. Alessandro Botton for handling all the editorial aspects concerning the publication of this volume. The Editorial Board