The Align-Define-Design-Refine (ADDR) process is a methodology for guiding organizations through complexities in API design and implementation, consisting of four key phases: align, define, design, and refine. ADDR helps establish the strategic purpose of an API, detail its capabilities, create its structure and user experience, and iterate based on feedback and testing. The process can be accelerated using Ambassador's Blackbird product, which reduces errors, improves consistency and reusability, decreases time-to-market, and drives positive business outcomes.