The main goal of CS3MESH4EOSC is to create an interoperable federation of data and higher-level services to enable friction-free collaboration between European researchers. This will be achieved by capturing the momentum of recent cloud service provisioning and uptake in National Research and Education Networks (NRENs) and public research sector providers across Europe. In particular, the availability of Enterprise File Synchronisation & Sharing (EFSS) services has led to an increase in data storage and collaboration opportunities for mid- to long-tail science, which we hope to further empower through a shared ecosystem of distributed research tools. The main goal of WP5 is to develop and implement a stakeholder-oriented dissemination and engagement strategy, to ensure CS3MESH4EOSC results are captured, disseminated and exploited. For this, the WP5 team interacts continuously with all project WPs and prepares consistent and content-rich outreach activities, by using multiple integrated communication tools. Guided by customised and strategic communication plans, the first 18-month period saw the first developments of CS3MESH4EOSC Key Exploitable Results (KERs) and the creation of community of stakeholders interested in the project core activity. The focus for the next 18-month period is to contribute actively to the KERs��� adoption by the various stakeholders and integration within the European Open Science Cloud (EOSC). The CS3MESH4EOSC ���D5.2 Interim report on dissemination and exploitation of project results��� is an updated version of ���D5.1: Communication and stakeholder engagement plan��� released in September 2020 (M9). This report documents the results and impact of communication efforts undertaken from September 2020 (M9 ��� month when Trust-IT joined the consortium and became WP5 leader) to June 2021 (M18), which focused on creating awareness about the CS3MESH4EOSC project, its goals, its ambition and the expected KERs. The document is divided in specific sections, listing the results achieved during this first reporting period: Section 1 gives an introduction of the KERs and the engagement results achieved so far; Section 2 lists the communication results from M1-M18 and indicates plans and goals for the next period; Section 3 provides an overview of CS3MESH4EOSC presence at third-party events, as well events organised by the project, along with other initiatives. Plans for the next period are also detailed; Section 4 describes how the project is liaising with the EOSC initiative; Section 5 is dedicated to the synergies established so far or otherwise planned, with different, related initiatives and projects; Section 6 provides a first overview of CS3MESH4EOSC exploitation plan; Section 7 lists a quick overview of the Key Performance Indicators (KPIs) achieved by M18, along with those to be achieved by end of the project; Section 8 includes a timeline of the Action Plan of activities from M18 till project end; Section 9 draws some overall conclusions and provides a concise overview of the coming 18-month period. All CS3MESH4EOSC communication and dissemination activities performed aimed to maximise the outreach, dissemination and exploitation impacts of the project during the first period, with the intent to have the same effect during the whole project lifetime and after its conclusion.