The “Foot-in-the-door” is a compliance technique which consists in proposing a little first request to a subject then to submit him/her a second more expensive request. In this way, more compliance to the second request is obtained than in a control situation where this request was not preceding by the first solicitation. Many investigations on this paradigm generally used an interaction in face-to-face or by phone. So, a experiment was carried out by means of the electronic-mail. Fifty students in computer science received a e-mail containing a 40 question survey on their food habits which required 15–20 min of their time. This questionnaire came from a hypothetical student of the university in which the subjects were registered. Thirty minutes before, half of the subjects, had responded to a small solicitation (information about file's conversion) made by this same solicitor. Results show that the compliance to the first request increased the likelihood of later compliance to the second, more costly request.