IFEFFIT was written with helpful suggestions from Julie Cross, Bruce Ravel, and John Rehr, and is based largely on the UWXAFS3.0 Package, written at the University of Washington under the direction of Edward Stern. More detailed acknowledgements and historical information can be found in the THANKS file distributed with IFEFFIT. Many of the features that make IFEFFIT useful and successful are from excellent feedback and suggestions given from the large community of users.