"Gamberini et al found that twice as many visitors gave up their information if they were able to access the information first. It’s counterintuitive, perhaps, but even though these visitors were under no obligation to complete the form, they converted at double the rate of visitors seeing the “mandatory” form." This study compares the relative effectiveness of two different persuasive strategies embedded in the rationale of a website. The visitor is asked for his/her contact information either prior to or after having access to the guidelines for managing multimedia files offered by the site. Asking for personal data prior to access represents a reward strategy for obtaining such data. In contrast, asking for personal data after access represents a reciprocity strategy. In addition, the mediating effect of website features displaying “social proof” (such as visits counter) is explored. The analysis of the amount and type of contact information provided shows that a persuasive strategy based on reciprocity is more effective than one based on reward. Also, the presence of social proof features seems counterproductive when using a reciprocity strategy, while it seems to improve the visitors’ compliance with the request when using a reward strategy. The results are discussed in terms of adequacy of the persuasive strategy to the specific website genre.