We want to find the optimal strategy for displaying advertisements e.g. banners, videos, in given locations at given times under some realistic dynamic constraints. Our primary goal is to maximize the expected revenue in a given period of time, i.e. the total profit produced by the impressions, which depends on profit-generating events such as the impressions themselves, the ensuing clicks and registrations. Moreover we must take into consideration the possibility that the constraints could change in time in a way that cannot always be foreseen.