The ESS environment is built on the open-source projects of many contributors, dating back to 1989 where Doug Bates and Ed Kademan wrote S-mode to edit S and Splus files in GNU Emacs.  Frank Ritter and Mike Meyer added features, creating version 2.  Meyer and David Smith made further contributions, creating version 3.  For version 4, David Smith provided significant enhancements to allow for powerful process interaction.

John Sall wrote GNU Emacs macros for SAS source code around 1990.  Tom Cook added functions to submit jobs, review listing and log files, and produce basic views of a dataset, thus creating a SAS-mode which was distributed in 1994.

In 1994, A.J. Rossini extended S-mode to support XEmacs.  Together with extensions written by Martin Maechler, this became version 4.7 and supported S, Splus, and R.  In 1995, Rossini extended SAS-mode to work with XEmacs.

In 1997, Rossini merged S-mode and SAS-mode into a single Emacs package for statistical programming; the product of this marriage was called ESS version 5.  Richard M. Heiberger designed the inferior mode for interactive SAS and SAS-mode was further integrated into ESS. Thomas Lumley's Stata mode, written around 1996, was also folded into ESS.  More changes were made to support additional statistical languages, particularly XLispStat.

ESS initially worked only with Unix statistics packages that used standard-input and standard-output for both the command-line interface and batch processing.  ESS could not communicate with statistical packages that did not use this protocol.  This changed in 1998 when Brian Ripley demonstrated use of the Windows Dynamic Data Exchange (DDE) protocol with ESS.  Heiberger then used DDE to provide interactive interfaces for Windows versions of Splus.  In 1999, Rodney A. Sparapani and Heiberger implemented SAS batch for ESS relying on files, rather than standard-input/standard-output, for Unix, Windows and Mac.  In 2001, Sparapani added BUGS batch file processing to ESS for Unix and Windows.

  * The multiple process code, and the idea for ess-eval-line-and-next-line are by Rod Ball.

  * Thanks to Doug Bates for many useful suggestions.

  * Thanks to Martin Maechler for reporting and fixing bugs, providing many useful comments and suggestions, and for maintaining the ESS mailing lists.

  * Thanks to Frank Ritter for updates, particularly the menu code, and invaluable comments on the manual.

  * Thanks to Ken'ichi Shibayama for his excellent indenting code, and many comments and suggestions.

  * Thanks to Aki Vehtari for adding interactive BUGS support.

  * Thanks to Brendan Halpin for bug-fixes and updates to Stata-mode.

  * Last, but definitely not least, thanks to the many ESS users and contributors to the ESS mailing lists.

ESS version 5 is being developed and currently maintained by

     [file authors.texi not included]