For Dick Tracy of comic-strip fame and Captain Kirk of ‘Star Trek’, voice communication from tiny equipment over vast distances posed no problem, but in the real world of 1986 the situation is much more difficult. Historically, mobile telephone systems using HF, VHF and UHF radio have been developed since the Second World War with military and commercial systems evolving in parallel. Although often the military needs have led the technological developments, more recently civil systems have been taking the lead in many areas. Initially voice communication by mobile radio operated in closed groups of users on an ‘all-informed’ basis, but, more recently, connection to the world's telephone network has been possible and incoming calls are automatically routed to mobile subscribers wherever they may be in the system—a real breakthrough in the concept of personal communication. But can this be extended ultimately to a worldwide system? And can the hardware really approach the convenience available to Dick Tracy and Captain Kirk? The paper considers some of the technical problems to be overcome in terrestial radio systems and touches on the prospects for satellites to play a role in this, but concludes that it will be some time before we can match the facilities available to our fictional heroes.