API product managers (PMs) are responsible for the commercial success of API products from ideation to design, build, launch, enhancement, and sunset. Although they share DNA with other PMs, API product management reflects the place of APIs in modern business. API PMs must cultivate a deep understanding of API customers, their needs, and the competitive landscape. They use key performance indicators (KPIs) to assess the value of their APIs and support marketing and sales teams with supplemental knowledge. They must have credibility with those who build and use APIs and be insightful to identify new customers and markets for offerings to drive business growth.