The article begins by reviewing recent work on music radio, much of which suggests that radio's processes of selection reinforce the success of existing and familiar artists and genres. Through examining the recent history of BBC Radio 1, I suggest that there are ways in which the music-selection and scheduling processes of radio may be used to lead (rather than entirely follow) public tastes. I include a small-scale comparative analysis of the 'airplay' of certain records on Radio 1 and its commercial rivals, together with an examination of Radio 1's recent scheduling and programming changes. I seek to draw out two implications from this analysis. Firstly, I argue that there is some support for Radio 1's rhetorical claims to have changed the British popular music environment in the mid-1990s. Secondly, I argue that the patterns of programming on Radio 1 are consistent with many of the BBC's stated public-service commitments, despite a popular and commercial perception of pop-music being inappropriate for the Corporation. However, I suggest that this public-service role is achieved, not through the usual habit of scheduling specialist music in the evenings, but by effecting a new permeability between the traditionally separate domains of daytime (mainstream) and evening (specialist) music programmes.