While there is a growing body of research on influencer marketing, it focuses almost exclusively on the consumer marketing context, and offers limited insights for business-to-business (B2B) organizations. To address this gap, the purpose of this study is to explore the use of influencer marketing in B2B markets. We draw empirical insights from 22 interviews with a) 12 senior marketing managers representing influencer marketing users in various B2B industries, ranging from industrial product manufacturers to professional service providers, and b) 10 experts from marketing agencies who advise other B2B firms on how to apply influencer marketing. The study findings identify the key elements of influencer marketing in B2B markets, and reveal four different strategies that B2B organizations use to operationalize the influencer marketing concept in practice. The study contributes to theory by providing the first empirical conceptualization of the B2B influencer marketing phenomenon. In doing so, the study widens the scope of influencer marketing to accommodate broader collaborations with influencers, which has significant implications across B2B and B2C contexts. For managers, this study offers alternative strategies to implement influencer marketing, which are associated with unique characteristics and serve different business goals.