Influencer marketing (a.k.a. influence marketing) is a form of social media marketing involving endorsements from influencers, people and organizations who have expert knowledge and social influence in a respective field. In China, influencers are known as key opinion leaders (KOLs; Chinese: 关键意见领袖; pinyin: guānjiànyìjiànlǐngxiù).
Influencer content may be framed as testimonial advertising where they play the role of a potential buyer themselves, or they may be third parties. These third parties exist either in the supply chain (retailers, manufacturers, etc.) or may be so-called value-added influencers (such as journalists, academics, industry analysts, and professional advisers).