In recent years investigation ofthe phenomenon of neurosecretion has proceed- ed largely along lines that emerged from the discussions of the first Symposium on Neurosecretion, held at the Zoological Station, Naples, Italy, in 1953 [Pubbl. Staz. Zool. 24, Suppl. 1-98 (1954)]. N ew insights were gained as a result of the use of the electron microscope. Con- siderable progress was made in the chemical analysis of the material produced and released by neurosecretory cells. The roele of neurosecretory centers in the neuro- endocrine control of various physiological functions in inverte bra tes and verte brates is understood a great deal better today than a few years ago. These and related topics were discussed at the Second Symposium on Neurosecretion, held at the University of Lund, Sweden, July 1-6, 1957. As in the case of the Proceedings of the Naples Symposium the manuscripts of the formal papers were collected by the editors some time after the meeting in order to enable the authors to include the essentials of the discussions which followed each paper. To record the discussions verbatim seemed less important than to risk the loss of spontaneity which might result from the presence of recording apparatus. The organization of such a meeting requires the dedicated cooperation of many persons and the good will of various agencies. The members of the Symposium were unanimous in their. praise and gratitude for their gracious hosts at Lund.