“The internet is greatly improving the impact of scholarly journals, but also poses new threats to their quality. Publishers have arisen that abuse the Gold Open Access model, in which the author pays a fee to get his article published, to make money with so-called predatory journals. These publishers falsely claim to conduct peer review, which makes them more prone to publish fraudulent and plagiarised research. This thesis looks at three possible methods to stop predatory journals: black- and white-lists, open peer review systems and new metrics. Black- and whitelists have set up rules and regulations that credible publishers and journals should follow. Open peer review systems should make it harder for predatory publishers to make false claims about their peer review process. Metrics should measure more aspects of research impact and become less liable to gaming. The question is, which of these three methods is the best candidate to stop predatory journals. As all three methods have their drawbacks, especially for new but high quality journals, none of them stop predatory journals on its own can. Rather, we need a system in which researchers, publishers and reviewers communicate more openly about the research they create, disseminate and read. But above all, we need to find a way to take away incentives for researchers and publishers to engage in fraudulent practices.”