One common way to share brand experiences is the selfie, a major trend in the context of user-generated content. Nevertheless, research on the effectiveness of user-generated content, and selfie campaigns in particular, is still scarce. In the context of selfie campaigns, participation (i.e. taking a selfie with the brand and posting it) represents one form of consumer engagement. Besides a behavioral reaction, selfie campaigns might also stimulate brand interest. To fill this research gap, the current research relates the mental-imagery-evoking potential of selfie campaigns to participation and brand interest, with both variables being assumed to mediate the impact of mental imagery on brand attitude. Findings yielded by one qualitative pilot study, one field study and an online survey confirm our theoretical reasoning that selfie campaigns prompt mental imagery, and that brand interest (but not selfie-campaign participation) influences brand attitude.