We have made available a Beta version of an auditing tool for assessing the effectiveness of an advertisement. It is called the AdPrinAudit and is located in the new section, “Evaluating Ads.” The Beta version is in the form of an Excel spreadsheet. It currently includes only brief descriptions of the principles. The audit allows one to calculate the “Armstrong Index” or “AI,” which is a measure of how well the ad follows evidence-based persuasion principles. The AI is calculated as the number of principles that were applied effectively minus the number that were violated. Work we have done over the past decade suggests that the AI provides a good way to identify which of a set of proposed ads will be most effective. Please send your suggestions for improvements to the software. We also hope that some of you will compare the AI against sales results for direct response ads and report the results on the AdPrin site.