The implementation of open access in the academic publishing system follows two paths, which are referred to as gold and green open access. The two paths complement each other in the sense that the former refers to first publications, while the latter is aimed at second publications. The following is a brief description of these two routes.

The golden path of Open Access publishing refers to the first publication of scientific works. This can take the form of an article in an open access journal, an open access monograph or a contribution to an open access anthology.

There are currently numerous pure Open Access journals. Many of them were previously closed access and have now been transformed. You can find an overview of them in the Directory of Open Access Journals. There is also an increasing number of publishers that now offer the possibility of publishing Open Access monographs or edited volumes.

Publication through the Gold Open Access path usually takes place against payment of the publication fees to the publisher. Authors can finance these costs in various ways, e.g. by including them in the costs of a third-party funded research project or by submitting an application to the university's research fund. Further information can be found on the page Funding.

Although the Gold Open Access route would be preferable, in some instances it is not possible to publish in this way. In such cases, the second option of publishing via Green Open Access is recommended.

^{Source: adapted from Oberländer, A. (2020). Open Access – Es ist nicht alles Gold, was glänzt. In: Open Science. Von Daten zu Publikationen. Zenodo. http://doi.org/10.5281/zenodo.4018594 (CC BY 4.0 International)}

The green path of open access publication (also known as self-archiving) refers to the re-publication of texts previously issued by a publisher (usually in closed access) on institutional or disciplinary open access repositories. This can take place simultaneously or following the original release by the publisher and is possible both for texts that have not yet undergone a review process (Preprint) as well as for those that have already successfully completed this process (Postprint or Version of record).

Publishing via the Green Open Access path can be done in various ways. One of the most common is the use of author's rights for so-called self-archiving. This allows authors to archive a version of their own article (usually only preprint or postprint) for public access after a certain period of time (embargo period).

^{Source: adapted from Oberländer, A. (2020). Open Access – Es ist nicht alles Gold, was glänzt. In: Open Science. Von Daten zu Publikationen. Zenodo. http://doi.org/10.5281/zenodo.4018594 (CC BY 4.0 International)}

Another option for publishing via Green Open Access is for authors to utilise their own rights of use. In order to release a manuscript through a publishing house, the authors conclude a contract with it in which they transfer part of their rights of use either on an exclusive or non-exclusive basis. In the case of exclusive use by the publisher, authors may only republish their publications if the contract with the publisher expressly authorises them to do so. If, on the other hand, the publisher has been granted a simple right of use, the authors are free to decide on the further use of their works.

In addition to the terms Gold and Green Open Access, the term Hybrid Open Access is also often used. In contrast to the two previous terms, this does not refer to an actual 'path' of publication. Instead, it is used to describe a type of scientific journal that is neither purely open nor closed access. These are usually subscription journals which also allow articles to be published in open access against payment of a publication fee (see also APC and BPC). For authors, this is therefore essentially an alternative implementation of Gold Open Access, in which their articles do not appear in a pure Open Access journal, but in a subscription journal.