In an age of party dealignment and electoral volatility the campaign strategies of parties – the assumptions they make about voting behaviour, the messages they seek to convey, the techniques they employ and so forth – will have a substantial impact upon electoral outcomes. Campaigning involves communication, that is ‘a planned effort on behalf of a sender to influence some or all groups in a society with a certain message or set of messages’ (Windahl, Signitzer and Olson, 1992: 19). Since the introduction of the mass media – newspapers, the radio and above all television – and the spread of new techniques of persuasion, derived from commercial advertising and marketing and first systematically used in the US, the communications system has altered tremendously. In 1955 the Conservatives became the first party to employ an advertising agency – a development scorned by Labour which, in 1959, explicitly repudiated modern media techniques and expertise (Rose, 1967: 63). But by the early 1960s Labour was exhibiting a keen interest in new methods of communication and in the 1964 election it recruited outside professionals to advise on communications methods, employed opinion research to identify target voters, strengthened its publicity department and used advertising to project its key election themes (Butler and King, 1965: 67-72; see also Rose, 1967). In addition, Wilson grasped the importance of television which he exploited in a masterly fashion.