This study explores the effects of interacting with three current interactive television (iTV) ad formats, using an Australian audience panel. Interaction with iTV ads has positive effects on awareness and net positive thoughts, which increase purchase intentions compared with the influence of regular ads. The telescopic format represents the best format, likely because it makes the most of the entertaining possibilities of iTV by offering additional long-form video; its superior performance cannot be explained readily by self-selection effects. The results suggest that the effectiveness of iTV ads should be measured by their interaction rate rather than the much smaller response rate, and iTV advertisers should consider ways to maximize interaction and response rates.