CALYPSO SOUTH addresses the challenges of safer marine transportation, protection of human lives at sea, and the safeguarding of marine and coastal resources from irreversible damages. It is a commitment to put technological advancement and scientific endeavour at the service of humanitarian responses, reducing risks in sea faring, and protecting the marine environment. CALYPSO SOUTH follows the trail of the previous CALYPSO and CALYPSO FOLLOW ON initiatives, with the overall objectives of i) extending the CALYPSO HF radar network coverage to the western part of the Malta-Sicily Channel and the southern approaches to the Maltese archipelago, ii) developing new monitoring and forecasting tools, and iii) delivering tailored operational downstream services to assist national responsible entities in their maritime security, rescue and emergency response commitments. The expected changes comprise intelligent ICT support to responsible entities to limit intervention times and narrow down search areas. Main outputs consist of weather stations for integrated port safety applications, additional HF radar stations to improve the coverage, quality and availability of data for targeted downstream services. Beneficiary responsible entities include the Armed Forces of Malta, Transport Malta, Civil Protection Departments (Malta/Sicily), Italian Coast Guard, and Marina Militare Italiana with the improvement of the efficiency, range and reliability of their operations in favour of superior security and safety at sea. In CALYPSO SOUTH a synergistic approach between Maltese and Sicilian partners is mandatory since the project objectives can be exclusively achieved through a cross-border approach due to the inherent and borderless characteristics of the topic. Indeed, the observed patterns of variability of sea currents and wind suggest that a hazard triggered in a site could threat the counterpart site; moreover security at sea largely involves trans-boundary waters. The proposed ICT network requires HF stations to be installed on both the Malta and Sicily sides. The project is a further building block towards the phased creation of permanent structures encompassing a comprehensive Marine Electronic Highway in the area