As radio stations in Europe tend more towards defining their target audience, by locality, demographics, or musical taste, the BBC World Service in English continues to pursue the opposite goal of a truly global audience united only by the ability to understand English and access to a radio set. On the air 24 hours a day, the network offers high quality international news reports and analysis, supported by a comprehensive range of music, entertainment and factual programmes to a weekly audience of 25 million listeners in a range of different countries, cultures, time zones and media environments. This paper uses examples from recent projects to illustrate the different ways that the BBCs International Broadcasting & Audience Research Department has attempted to find valid solutions to diverse research problems. We combine commissioned surveys, focus groups, postal questionnaires and diaries. We are not always successful, and our picture of the World Services English language audience is still a jigsaw with many pieces missing. But we have learnt how to make the most of limited resources to produce findings that the programme makers can both trust and act on.