The following is a list of those who have contributed significant code to the Inno Setup project, or otherwise deserve special recognition:

• Jean-loup Gailly & Mark Adler: Creators of the zlib compression library that Inno Setup uses.
• Julian Seward: Creator of the bzlib compression library that Inno Setup uses.
• Igor Pavlov: Creator of the LZMA compression library that Inno Setup uses.
• ?: Most of the disk spanning code (1.09). (Sorry, somehow your name was lost!)
• Vince Valenti: Most of the code for the "Window" [Setup] section directives (1.12.4).
• Joe White: Code for ChangesAssociations [Setup] section directive (1.2.?).
• Jason Olsen: Most of the code for appending to existing uninstall logs (1.3.0).
• Martijn Laan: Code for Rich Edit 2.0 & URL detection support (1.3.13); silent uninstallation (1.3.25); system image list support in drive and directory lists (1.3.25); silent installation (2.0.0); [Types], [Components] and [Tasks] sections (2.0.0); postinstall flag (2.0.0); [Code] section (4.0.0); Subcomponents and subtasks support (4.0.0); Many other features after 4.0.0.
• Alex Yackimoff: Portions of TNewCheckListBox (4.0.0).
• Carlo Kok: RemObjects Pascal Script (4.0.0).
• Creators of SynEdit: The syntax-highlighting editor used in the Compiler (2.0.0).
• Creators of UniSynEdit: The syntax-highlighting editor used in the Compiler (5.3.0).
• Creators of Scintilla: The syntax-highlighting editor used in the Compiler (5.4.0).
• glyFX: The Inno Setup logo, the compiler icon, the document icon, the Inno Setup installer wizard images and the images for the IDE's toolbar. 128x128 and 256x256 icon sizes by Motaz Alnuweiri.
• Zaher Dirkey: Initial work on improved right-to-left languages support.
• Evgeny Karpov of RemObjects Software: Initial work on Unicode support.