A key task for advertising media planners is setting a frequency goal for a campaign. This study used a controlled experiment to identify the minimum effective frequency (MEF) for TV ads offering interactive response, as opposed to direct response by phone call. Participants ( N = 273) were exposed to ads one, three or fi ve times. A control cell saw normal TV ads, while an interactive TV (iTV) cell saw the same ads with interactive response banners superimposed. We found the usual ' build-up ' effects for repeated exposure on ad memory in the control cell, but there was little added value in repeat exposure for generating interactive response (ie MEF = 1). Interaction rates were higher for familiar brands, but brand familiarity did not alter the effect of repetition. These results suggest that iTV ads should be placed with a reach strategy, rather than a frequency strategy.