Physiology. In the article “Activation of heteromeric G protein-gated inward rectifier K⁺ channels overexpressed by adenovirus gene transfer inhibits the excitability of hippocampal neurons” by Markus U. Ehrengruber, Craig A. Doupnik, Youfeng Xu, Justine Garvey, Mark C. Jasek, Henry A. Lester, and Norman Davidson, which appeared in number 13, June 24, 1997, of Proc. Natl. Acad. Sci. USA (94, 7070–7075), the authors wish to correct the institutional affiliation of Dr. D. E. Clapham, which was printed incorrectly on page 7070 as McMaster University. Dr. Clapham’s correct affiliation is Harvard University Medical School.