Business friendships are increasingly common. Research in organizational behavior has identified a number of benefits to career and organizational performance of these relationships. These instrumental benefits derive from the affective qualities of these relationships, through the mechanisms of trust, empathy and sympathy. Yet the combination of instrumentality and affect produces a number of difficulties for business friends. Business friendships represent potential threats to the self-concept of friends if they obtain differential business outcomes; they involve the exchange of resources which are incompatible; and they represent contrasting norms of reciprocity. We also present new evidence that people prefer affective and instrumental relationships to be embedded in very different network structures. This evidence presents a non-trivial challenge to embedding business friendships, which represent both affect and instrumentality. We recommend that the field respond to these challenges by considering the impact of business friendships on broad outcome variables such as well-being that may reflect both the benefits and tensions of those relationships, and by evaluating the approaches available to effectively manage business friendships.