Greenstone is a suite of software for building and distributing digital library collections. It is not a digital library but a tool for building digital libraries. The software provides a way of organizing information and publishing it on the Web in the form of a fully-searchable, metadata-driven digital resource. It can also be run in a non-networked environment (standalone), operating from removable media such as a USB Flash Drive and DVD. Greenstone has been developed and distributed in cooperation with UNESCO and the Human Info NGO in Belgium. It is open-source, multilingual software, issued under the terms of the GNU General Public License. In 2004 its developers received the IFIP Namur award for "contributions to the awareness of social implications of information technology, and the need for an holistic approach in the use of information technology that takes account of social implications."



There are two major versions of the software.

Greenstone3 is a complete redesign and reimplementation of the original digital library software we developed back in 2000 (Greenstone2). It incorporates all the features of the previous software, and is backwards compatible. An import 'Greenstone2 collection' feature is provided in the Greenstone Librarian Interface (GLI) to assist in the transition to the new software for existing users. Greenstone3 is written in Java and takes advantage of many web technologies—such as XML Transforms (XSLT), and the Java Authentication and Authorization Service (JASS)—which have emerged since we first started developing digital library software. This makes the digital library software highly customizable and extensible in the functionality it delivers. In contrast, Greenstone2 was written in C++ and had to make heavy use of bespoke formats and syntax we devised ourselves. This was because of the lack of available web technologies at the time, meaning not only was the functionality it provided more limited, the bespoke syntax meant users were completely reliant on us providing documentation detailing how things worked.

Greenstone3 is under active development, and is recommended for download. We also provide maintenance releases for its forerunner, Greenstone2.


Greenstone runs on all versions of Windows, Unix/Linux, and Mac OS-X. It is very easy to install. For the default Windows installation absolutely no configuration is necessary, and end users routinely install Greenstone on their personal laptops or workstations. Institutional users run it on their main web server, where it interoperates with standard web server software (e.g. Apache for Greenstone2, Tomcat for Greenstone3). An experimental version is also available for Android: that is a version where the digital library operates self-contained on the user’s phone or tablet.


Greenstone is highly interoperable using contemporary standards, It incorporates a server that can serve any collection over the Open Archives Protocol for Metadata Harvesting (OAI-PMH), and Greenstone can harvest documents over OAI-PMH and include them in a collection. Any collection can be exported to METS (in the Greenstone METS Profile, approved by the METS Editorial Board and published at http://www.loc.gov/standards/mets/mets-profiles.html), and Greenstone can ingest documents in METS form. Any collection can be exported to DSpace ready for DSpace's batch import program, and any DSpace collection can be imported into Greenstone.


Greenstone has two separate interactive interfaces, the Reader interface and the Librarian interface. End users access the digital library through the Reader interface, which operates within a web browser. The Librarian interface is a Java-based graphical user interface that makes it easy to gather material for a collection (downloading it from the web where necessary), enrich it by adding metadata, design the searching and browsing facilities that the collection will offer the user, and build and serve the collection. The Librarian interface can be configured to manage remote Greenstone installations. Greenstone3 also provides library management facilities that are built in to the web browser interface (once the user has logged in)—an advantage over the previous version of the software.


One of Greenstone's unique strengths is its multilingual nature. The reader's interface is available in over 60 languages, including Amharic, Arabic, Armenian, Bengali, Bulgarian, Burmese, Catalan, Chinese (both simplified and traditional), Croatian, Czech, Dari, Dhivehi, Dutch, English, Farsi, Finnish, French, Gaelic, Galician, Georgian, German, Greek, Gujarati, Hebrew, Hindi, Hungarian, Indonesian, Italian, Japanese, Kannada, Kazakh, Kyrgyz, Laotian, Latvian, Malayalam, Maori, Marathi, Mongolian, Nepali, Polish, Portuguese (BR and PT versions), Pushto, Romanian, Russian, Serbian (Cyrillic and Latin versions, and Bosnia Herzegovina Cyrillic and Latin versions), Sinhalese, Slovak, Spanish, Tamil, Telugu, Thai, Tigrinya, Turkish, Ukrainian, Urdu, and Vietnamese. The Librarian interface is available in over 20 languages, including Amharic, Arabic, Armenian, Catalan, Chinese (simplified), English, Farsi, French, Greek, Gujarati, Japanese, Kannada, Kazakh, Latvian, Marathi, Mongolian, Nepali, Romanian, Russian, Spanish, Tamil, Thai and Vietnamese. We are always looking for volunteers to add new language interfaces and help maintain existing ones.

Metadata formats

Users define metadata interactively within the Librarian interface. These metadata sets are predefined:

  • Dublin Core (qualified and unqualified)
  • RFC 1807
  • NZGLS (New Zealand Government Locator Service)
  • AGLS (Australian Government Locator Service)

New metadata sets can be defined using Greenstone's Metadata Set Editor. "Plug-ins" are used to ingest externally-prepared metadata in different forms, and plug-ins exist for: CSV, XML, EXIF, MARC, CDS/ISIS, ProCite, BibTex, Refer, OAI, DSpace and METS.

Document formats

Plug-ins are also used to ingest documents. For textual documents, there are plug-ins for: PDF, PostScript, Word, RTF, HTML, Plain text, Latex, ZIP archives, Excel, PPT, Email (various formats) and source code. For multimedia documents, there are plug-ins for: Images (any format, including PNG, JPEG, JPEG 2000, GIF, TIFF), MP3 audio, Ogg Vorbis audio, and a generic plug-in that can be configured for audio formats, MPEG, MIDI, etc.

User base


As with all open source projects, the user base for Greenstone is unknown. It is distributed on SourceForge, a leading distribution centre for open source software.

Distributed via SourceForge since: 11/2000
Average downloads per month since then: 5000
Currently running at: 3800
Total number of downloads (as at 1 June 2015): 949156
Software downloads proportion Windows / Linux / Mac / Source: 76% / 13% / 8% / 3%
Number of countries downloaded from: 170
Number of people on Greenstone email lists: 770


Examples of public Greenstone collections are found on the examples (greenstone.org/examples) page.

User Survey

Here are the results of a Greenstone user survey undertaken by Laura Sheble of the University of North Carolina in 2009. Survey participants included people that developed, used, studied, taught, promoted, and supported the Greenstone software.

UN agencies

with an interest in Greenstone include

  • UNESCO, Paris
    Sponsors distribution of the Greenstone software as part of its Information for All programme
  • Food and Agriculture Organization (FAO), Rome
    The Information Management Resource Kit uses Greenstone as the (only) example of digital library software in the Digitization and Digital Libraries self-instructional module (http://www.imarkgroup.org)
  • Institute for Information Technology in Education (IITE), Moscow
    Have commissioned an extensive course on Digital libraries in education that uses Greenstone for all the practical work
  • United Nations University (UNU), Japan
    Two CD-ROM collections of UNU material have been produced

Humanitarian collections

Greenstone is used by the Human Info NGO in Belgium to produce collections of humanitarian information which are distributed on CD-ROM widely throughout the developing world. For example, the Humanity Development Library contains 1,230 publications ranging from accounting to water sanitation. It runs on minimal computing facilities such as those typically found in developing countries. The information can be accessed by searching, browsing by subject, browsing by titles, browsing by organisation, browsing a list of how-tos, and by randomly viewing the book covers. (For more information, contact Michel Loots [email protected])

Number of humanitarian collections: ~40
Annual distribution of each one: ~5,000


Training is a bottleneck for widespread adoption of any digital library software. Many international training courses have been run; the Workshop Map (greenstone.org/map) shows a list of locations.