The OPERAS-PLUS project will support the further development of OPERAS in its preparatory phase of new ESFRI Research Infrastructure projects. OPERAS is the Research Infrastructure dedicated to enhance open scholarly communication for the Social Sciences and the Humanities in the European Research Area (ERA). Designed as a distributed infrastructure, it was incorporated as an AISBL in 2019. OPERAS entered the ESFRI roadmap in 2021 and is now on its path to become operational as an ERIC in 2028. The OPERAS-PLUS project will serve the OPERAS community with its wide variety of small-sized stakeholders, which are committed to make open scholarly communication the default practice in Social Sciences and Humanities in the ERA. In that sense, OPERAS-PLUS will provide an operational and efficient framework to meet the needs and objectives of the OPERAS community with solutions of utmost quality, thus fulfilling the European Commission‘s expectations of scientific excellence. The project’s main objectives are 1) to develop and strengthen OPERAS governance structure, especially financial, legal, and human resource management aspects of the infrastructure central hub in a sustainable way, compliant with Research Infrastructure management best practises; 2) to support the establishment and development of OPERAS national nodes, set up and manage the workflow of bidirectional exchange with the central hub; 3) to develop OPERAS portfolio of services by providing both required technology and a monitoring system for services development via an Innovation Lab dedicated to this task; and 4) to maximise OPERAS’ impact in the ERA and at an international level by extending it beyond its current scope and onboarding new members and countries in the infrastructure.