In the last years, free and open source software (also sometimes termed libre software) has gathered increasing interest, both from the business and academic worlds. As some projects in different application domains like most notably the operating system Linux together with the suite of GNU utilities, the office suites GNOME and KDE, Apache, sendmail, bind, and several programming languages have achieved huge success in their respective markets, both the adoption by commercial companies, and also the development of new business models by corporations both small and large like Netscape or IBM have increased. Given this situation, it did not take a long time for the discussion surrounding this new phenomenon to reach public organizations. Especially the most prominent example, the choice between a free operating system like GNU/Linux or a commercial system like Microsoft Windows has sparked interest in this new form of software, its legal and economic implications, and its new model of software development. In this article, these implications will be explored, explicitly not focusing solely on the Linux vs. Microsoft debate. To this end, an introduction to free/libre/open source software (FLOSS) and its concepts will be given, then different aspects of the relationship between FLOSS and public organizations, especially e-government, together with future trends will be discussed.