In combination with a customized support provided by the BBMRI-ERIC Common Service ELSI Helpdesk, the ELSI Knowledge Base will be available to the user on a self-serve basis. The knowledge base provides users with a first orientation on the subject matter, as well as allowing them to explore more detailed information if desired in a self-service manner. It is crucial that the information and knowledge provided are shared in a manner that is user friendly. Long lists of links, legalistic language, and multiple links have to be avoided wherever possible. The long-term sustainability and accuracy of a knowledge base need to be ensured by placing its expert curation and technical maintenance under the responsibility of an organization rather than a research consortium. In its core, it builds on a scenario-based approach using a non-legalistic language. In addition, the knowledge base connects to frequently asked questions, promotes contract and informed consent templates, how-to-guides, best-practice models, and scripts. The ELSI Knowledge Base is a key element of the BBMRI-ERIC Common Service ELSI, which currently serves biobanks but will be enlarged to serve the biological and medical sciences community. In contrast to the ELSI Helpdesk, which provides customized support, the ELSI Knowledge Base is available to the user on a self-serve basis. The conceptualization of the ELSI Knowledge Base builds on assessments of several ethical, legal, and societal guidance tools that favor a single sustainable knowledge base for closing the knowledge gap by providing practical hands-on guidance for researchers. Ultimately, the ELSI Knowledge Base aims at promoting practical know-how and skills for conducting responsible research. The ELSI Knowledge Base is a key element of the BBMRI-ERIC Common Service ELSI, which currently serves biobanks but shall be enlarged to serve the BMS community. In contrast to the ELSI Helpdesk, which provides customized support, the ELSI Knowledge Base is available to the user on a self-serve basis and expected to be fully operable in autumn 2018.