Although the information‐seeking literature has tended to focus upon the selection and use of inanimate objects as information sources, this research follows the more recent trend of investigating how individuals evaluate and use interpersonal information sources. By drawing from the structural, relational, and cognitive elements of social capital theory to inform antecedents to information quality and source accessibility, a research model is developed and tested. For interpersonal information sources, information quality is the key determinant of source use. Perceptions of information quality and accessibility of an interpersonal source are shown to be influenced by boundary spanning, transactive memory, and content type. Implications and prescriptions for future research are discussed.