ARTES 3-4 is the ESA-Industry Programme for satellite telecommunication product developments. ARTES 3-4 operates with a 'Call for Proposals' which is always open. The industry responds with proposals as they find it opportune. The activities proposed in response to this 'Call for Proposals' must be relevant for the satellite telecommunications sector: space segment, ground segment and applications involving telecommunication satellites. The content of an ARTES 3-4 contract consists of activities which have been identified by industry, ESA or national authorities as having clear applications potential. Essential characteristics of this programme are the proactive role of the Bidder in defining and proposing projects oriented to sustainable products (equipment, software, systems, applications, services) in the wide area of satellite telecommunications and the sharing of funding by ESA and industry/businesses for the development of the products. Although not a competitive tender action, the ARTES 3-4 Call for Proposals is published among these in order to achieve a higher degree of visibility. The closing date above has been established solely for technical reasons connected with EMITS and ought to be ignored. NOTE: THE PRESENT CALL FOR PROPOSALS REPLACES THE PREVIOUS ARTES 4 CALL FOR PROPOSALS (PUBLISHED UNDER REF.NO. AO4780).