Abstract
The paper aims to demonstrate opportunities which open source and free software or its principles can bring to libraries and other memory institutions. The first part of the paper focuses on key features of open source and free software.
Legal aspects and possible benefits for libraries using this type of software are underlined. The second part of the paper briefly introduces selected free software projects which are used in libraries.
The final part is dedicated to principles which are applied in free software and which can also be used in library (and other memory institutions) practice, with a special regard to long-term sustainability and to mitigating risks of losing investments in information technologies.