Open access (OA) journals are online journals whose articles are accessible free of charge and other barriers immediately upon publication. As journals that meet this definition do not require authors to transfer copyright to them, the articles are usually released under an open licence granted by the author. At the same time, there are many journals who make their content available for use free of charge but who do not grant open licences. OA journals are the primary medium of the so-called "gold road to open access".

The OA mode of publishing supports desired characteristics of journal publications: the articles achieve maximum dissemination; they are accessible to scholars and scientists and all other interested parties as quickly as possible; and research findings enjoy greater visibility, with the positive result that they are cited more frequently.

The main difference between OA- and non-OA journals lies in this free accessibility and usability of the articles. Otherwise, OA journals hardly differ from other journals: the articles are primary publications and, as a rule, they undergo a process of quality assurance - usually peer review - before publication. However, electronic publishing and new trends also enable other procedures such as open assessment to be conducted after publication of the first version of the work. To the extent that it was hitherto the norm in the discipline in question, some journals also practise a form of editorial review. While an OA journal is not per se qualitatively better (or worse) than a closed-access journal, OA contributes to quality assurance in a decisive way because ease of access to the works facilitates the discovery of errors - and plagiarism.

The journal impact factor (JIF), which is used to assess the quality of journals, has recently come in for increased criticism because it is not a very meaningful indicator and it is also susceptible to manipulation. The Hirsch index, or h-index, provides greater insight into citations of the works of individual authors but does not allow any conclusions to be drawn about journals as a whole. The umbrella term for approaches that capture the multiple ways in which scientists refer to works is altmetrics.

There are major differences between the business models employed by conventional journals and OA journals. What counts for readers, and especially for their institutions, for example university libraries, is the fact that neither they nor anybody else must pay to read or use the articles, which relieves the burden on libraries' acquisition budgets. At the same time, however, even OA journals cannot carry out all their work free of charge. Hence, alternative funding models are called for.

Articles published in OA journals are indexed at many locations and are frequently accessible via the usual databases and search engines. The BASE search engine specialises in OA content. Existing OA journals can be searched via the Directory of Open Access Journals (DOAJ).

Besides publishing in OA journals, there are other ways in which OA can be provided to journal articles. Articles published in non-OA journals can usually be posted to an OA repository in order to make them accessible there free of charge. However, many publishers allow access to be granted only after an embargo period has expired. Self-archiving rights are  increasingly being regulated within the framework of licensing negotiations (e.g. Alliance and National Licences). Moreover, some closed-access journals offer their authors the option of paying an article processing charge (APC) in order to provide OA to their contributions. These journals are known as "hybrid journals".

Finding Open Access journals

The central database for OA journals is the Directory of Open Access Journals (DOAJ). The search engine JURN is dedicated to indexing journals in the arts and humanities. Colleagues are often a good source of information on the OA journals in one's own field. The discipline-specific introductions provided here at are also a good starting point.

In general databases of journals and articles, filter options can be used to restrict one's search to content that is "gratis OA" (i.e. free of charge but not necessarily free of copyright and licensing restrictions) or even "libre OA" (i.e. free of charge and free of at least some copyright and licensing restrictions). Examples of databases that offer an OA filter include the Electronic Journals Library (EZB) (the "freely available" option), and the Web of Science.

"OA journal" is not a clearly defined term and - often for marketing reasons - the imprecise use of "open access" persists here, too.

Founding an Open Access journal

If you have an idea for a new OA journal, there are several possible options open to you. If the journal is to be published under the umbrella of a large scholarly publisher, you should get in touch with the publisher directly. Before doing so, you can consult the Directory of Open Access Journals (DOAJ) to find out whether the publisher's portfolio includes OA journals. At many universities you can also digitally publish your publication series via the university's institutional repository. The relevant contact persons provide on-site support.

If you wish to found an independent OA journal in collaboration with scientists from other institutions and to publish it yourselves, Open Journal Systems, (OJS) can be recommended. The freely available open source software OJS assists with every stage of the editorial and review process and offers detailed rights management, layout options, various roles (reader, author, editor , copy editor, layout editor, reviewer), and an OAI-PMH interface for the dissemination of the article metadata in search engines and (library) catalogues.