Physiology. In the article “Post-priming actions of ATP on Ca²⁺-dependent exocytosis in pancreatic beta cells” by Noriko Takahashi, Takashi Kadowaki, Yoshio Yazaki, Graham C. R. Ellis-Davies, Yasushi Miyashita, and Haruo Kasai, which appeared in number 2, January 19, 1999, of Proc. Natl. Acad. Sci. USA (96, 760–765), the following corrections should be noted. On page 761, left column, line 11 should read “2-nitrophenyl-EGTA” instead of “DMNPE-4.” Also, on page 765, left column, lines 11–15 should read “(ii) glucose increased insulin exocytosis, even when [Ca²⁺]_i was clamped at a high level and K_ATP channels were open (9, 11). These observations can be explained readily by the ATP-sensing mechanism identified in the present study.”