This thesis investigates different characteristics and dimensions related to social media influencers that might affect some brand outcomes after being endorsed by /collaborating with the influencer in brand communications. This study specifically examines the impact of three dimensions—social media influencer credibility, attractiveness, and endorsement content quality—on the collaborating brand’s credibility. It also examines the influence of brand credibility on brand advocacy. The study also explores the mediating role of brand credibility and the moderating role of digital experience. To achieve these aims, the researcher employed the premises of two theories: the stimulus–organism–response theory and the social learning theory. The data were collected using an online questionnaire from 281 respondents. The findings reveal that social media influencer credibility significantly influences the credibility of the collaborating brand which in turn exert significant impact on brand advocacy. A mediating effect of collaborating brand credibility is identified between social media influencer credibility and brand advocacy. The findings have essential managerial implications that assist managers in choosing the most effective social media influencer for their brand
