Participants in an interactive environment implemented by computer networks and other media such as interactive television are recruited to advertise products and brands to the other participants and viewers that are users of the media. Each participant may select from a set of available advertisements, which can be displayed in association with the user's avatar, virtual space and virtual objects within or embodying the virtual world. Participants are given incentives to do this by the availability of rewards, such as coupons, real or virtual money or other resources, which are provided by the advertising sponsors, based on adoption of the advertising by the participant, as well as on factors such as exposure of the selected advertisements to other users. Allowing the users to exercise advertising choice, as participant or viewer, the invention also facilitates collection of data regarding consumer preferences.