Finding and reusing train-the-trainer materials in Social Sciences and Humanities: The SSH Training Discovery Toolkit The Training Discovery Toolkit is an inventory of various learning and training materials that trainers of different disciplines in the Social Sciences and Humanities (SSH) can use to find materials for re-use in their own training activities. The Toolkit links to a variety of materials available through various sources on topics including Open Science, Research Data Management, and didactics, but also specific topics that are relevant to multiple disciplines, like text encoding and spatial data. While it primarily targets trainers, the Toolkit also contains information on other learning and training materials available for the SSH communities. The Toolkit is designed in close collaboration with the SSH Training Community to make available training resources discoverable and encourage re-use and exchange. Thereby the Toolkit helps to make the process of training preparation and delivery more efficient and effective. The toolkit is continuously updated and improved in its content and functionality, based on the feedback from users and the Training Community to best serve the learning and training needs in the SSH domain. We organize dedicated bootcamps to test the Toolkit and collect feedback which will be incorporated in the next version. In this poster, we give an overview of the Training Discovery Toolkit through example use cases. We will demonstrate its current content and the future plans to further develop it as a tool for training discovery in the EOSC. The Toolkit currently contains more than 70 items from 41 different sources on a range of topics for better development and implementation of training activities. The lack of quick availability of relevant training materials is often what prevents SSH trainers from developing relevant training programmes. The Training Discovery Toolkit addresses this gap by providing access to effective and often ready-to-go training programmes. In the long run, we hope the tool will make training on Open Science easy enough for it to advance to all European SSH communities, thus shifting the current research culture towards Open Science. The Toolkit is continuously updated based on the feedback from the SSH Training Community, which is collected at dedicated bootcamps and other relevant events. In 2021 new materials for trainers in the SSH domain on the services offered through EOSC will be created. The tool is also being updated taking into consideration the work of other international initiatives including the EOSC working group on skills and training, as well as the RDA IG Education and training on handling of research data and the EOSC Enhance project. For the final version of the Toolkit we aim to align the collected metadata for the various training resources with metadata models developed within the EOSC and dedicated RDA groups to ensure that the information in the Toolkit is interoperable and can be integrated into other services. We envision the Toolkit to become part of the larger services available for scholars through the European Open Science Cloud.