mcrypt and libmcrypt was originaly created by Nikos Mavroyanopoulos <nmav@hellug.gr>,
although many people contributed by sending bug reports, patches, and comments.

- Sascha Schumann <sascha@schumann.cx> 
- Steve Underwood <steveu@infowebtelecom.com> 
- Igor Schein <igor@txc.com>
- Alexander Demenshin <aldem@techie.com>
- Koblinger Egmont <egmont@fazekas.hu>
- Larry Snyder <larrys@lexis-nexis.com>
- Robin Humble <rjh@pixel.maths.monash.edu.au>
- Janusz A. Urbanowicz <alex@bofh.net.pl>
- Dan Stromberg <strombrg@nis.acs.uci.edu>
- R Sriram <rsriram@krdl.org.sg>
- Robert Hanzlik <robi@junyks.cz>
- Lars Nordentoft <lntech@post9.tele.dk>
- Don Sutherland <dss@yadda.net>
- Salvatore Sanfilippo <antirez@linuxcare.com>
- Jerome Bertorelle <jerome.bertorelle@noos.fr>
- Andrew Libby <alibby@commnav.com>
- Jonathan Woolmington <jwool@ind.tansu.com.au>
- Sami Farin <sfarin@ratol.fi>
- Barton C Massey <bart@cs.pdx.edu>
- Derick Rethans <d.rethans@jdimedia.nl>
- Phillip Oleson <poleson@verio.net>
- Bernard Guillot <bguillot@incoretech.com>
- Stefan Hetzl <shetzl@teleweb.at>
- Gustavo Niemeyer <niemeyer@conectiva.com>
- Germano Rizzo <mano@pluto.linux.it>
- Ilia A. <ilia@prohost.org>
- [and several others]

The Designers of the algorithms:

- DES: IBM & NSA 
- Lucifer (the algorithm that DES is based on): Roy Adler, Don Coppersmith, 
  Horst Feistel, Edna Grossman, Alan Konheim, Carl Meyer, Bill Notz, 
  Lynn Smith, Walt Tuchman and Bryant Tuckerman
- CAST-128/CAST-256: Carlisle Adams
- xTEA: David Wheeler & Roger M. Needham 
- 3-WAY: Joan Daemen
- Blowfish: Bruce Schneier
- Twofish: Bruce Schneier, Doug Whiting, John Kelsey, Chris Hall, David Wagner
- GOST: A.Zabotin, G.P. Glazkov, and V.B. Isaeva
- SAFER: J.L. Massey
- RC2/RC4: Ron Rivest
- LOKI97: Lawrie Brown, Josef Pieprzyk