Quantum GIS is an open source software project licensed under GNU General Public License. Development is done by a dedicated team of developers, documenters and supporters. The QGIS Project is always looking for volunteers to join the different teams and contribute to this wonderful open source project! Below you find some hints where to start.
Are you a C++ and/or Python programmer with knowledge of Qt (www.trolltech.com) and GIS? You can help QGIS become better by submitting bug fixes and patches. We look particularly favourably on bug fixes for issues related to the LTS (Long Term Supported) release branch (patches for these will be given priority).
Packaging and platform specific help
If you are able to package and maintain a platform specific port of QGIS, the release-team would like to hear from and provides an overview at the Wiki Release Info area. You would need to be familiar with the peculiarities of your operating system and probably will need to have some C++ knowledge to in the event that platform specific code needs to be run. Skills in the following areas are useful:
Non programming help
Are you a non-coder and interested to help? The QGIS community-team always needs volunteers keeping the documentation current with new developments in the code base, translating it to different languages, adding examples, updating screenshots, maintaining the QGIS website, forum and blog. Read through the Wiki Community Resource area for more information.