Co-promotion agreements and a wide variety of strategic alliances are redefining the pharmaceutical industry. Yet interviews with 28 executives from 12 companies that have chosen or are seeking a pharma partner to market a late-stage compound confirm a disturbing fact: Despite much executive-suite talk about becoming the "partner of choice," few companies have devoted the resources needed to build alliance infrastructures that will support the entire portfolio of co-promotion deals, licensing agreements, R&D collaborations, and other relationships that are quietly reshaping their organizations.