Present research builds upon native advertising research by examining the roles of advertising message relevance, consumer-brand relationship strength, and authorship. Two national experiments were conducted among active Twitter users ages 18-34. In Study 1 (N = 147), a 2 (disclosure: tweet/promoted tweet) X 2 (high-/low-ad message relevance) experiment showed that while disclosure had no effect on advertising outcomes, strong message relevance effects were present. Study 2 (N = 363), a 2 (weaker/stronger brand relationship strength) X 2 (disclosure: tweet/promoted tweet) X 3 (authorship: brand/influencer/peer) design, found that consumer-brand relationship strength also directly and positively influences attitude towards the brand, purchase intention and sharing intention; while significantly enhancing the positive message relevance impact on sharing intention, relevance's impact on purchase intention was lessened. Greater consumer-brand relationship strength influence on attitude towards the brand and purchase intention was present when native ads were authored by peers rather than brands or influencers.