Measuring effectiveness of online ads is of critical importance to the survival of the Web as an advertiser-supported medium. Present efforts in measuring performance of Web ads are concentrated on adapting measures used in traditional media to the online medium. However these measures do not take into account the unique interactive characteristics of the medium and the differences in how consumers process advertising stimuli on the Web. Further, ad processing and performance measurement capabilities differ across various advertising formats on the Web. This research proposes a framework to investigate how consumers interact with different advertising formats on the Web and identify metrics that reflect how effectively the ad is processed.