Microbiology. In the article “Molecular and biophysical characterization of TT virus: Evidence for a new virus family infecting humans” by Isa K. Mushahwar, James C. Erker, A. Scott Muerhoff, Thomas P. Leary, John N. Simons, Larry G. Birkenmeyer, Michelle L. Chalmers, Tami J. Pilot-Matias, and Suresh M. Dexai, which appeared in number 6, March 16, 1999, of Proc. Natl. Acad. Sci. USA (96, 3177–3182), the following correction should be noted. The last author’s name has been misspelled, and it should be amended as Suresh M. Desai and not Suresh M. Dexai.