Nowadays secure and protected radio-communications – especially at sea – are more important than ever. Mobile naval forces require reliable, jam-resistant and secure voice and data connections. Standardised communication media has long been part of today’s naval communications and are now indispensable. Manufacturers specialising in tactical radio-communications offer state-of-the-art solutions that will soon be standard on naval vessels with up-to-date equipment. Today, many of these methods can be implemented in software-defined radios. In radio-communications, interoperability is a particularly important aspect with multinational forces. It is also a must in the co-operation with allied nations in joint combined operations and partnership for peace (PfP) missions. Prerequisites are standardised waveforms, protocols and methods. The use of digital software radios ensures this right from the beginning. Modern systems for radio monitoring and radiolocation are frequently integrated into the communications system. In addition to well-known transmission media, satellite broadcast systems (SBS) and global broadcast systems (GBS) will soon open up completely new prospects. The trend in naval communication systems is toward a comprehensive integrated information monitoring, command and weapons system.