In his new book, Corporate Diplomacy: Building Reputations and Relationships with External Stakeholders , Wharton management professor Witold Henisz advises senior managers to build the capability to strategically develop their most important relationships — before it’s too late. In an interview with Wharton management professor Stephen J. Kobrin , Henisz explains how to determine who are the most important stakeholders to focus on and how to avoid the mistakes made by companies that have lost more than 0 million by failing to develop relationships with external stakeholders. An edited transcription of the conversation follows. Stephen J. Kobrin: What is “corporate diplomacy”? Witold Henisz: Corporate diplomacy is the senior-level capability to build and maintain relationships with external stakeholders and deliver on the greatest needs or the greatest objectives of those stakeholders in a way that delivers shareholder value. Kobrin: Why is it important?…