DMAIC, DMADV, and Agile methodologies all evolved from concepts like Deming's work in post-war Japan and the Toyota Production System. They provide structured approaches for process improvement and new product development. DMAIC follows the phases of Define, Measure, Analyze, Improve, and Control for operational process improvement using Lean and Six Sigma tools. DMADV is similar but used for new product Design and Verification. Agile focuses on iterative product delivery and can complement DMAIC/DMADV. The role of the business analyst is evolving to incorporate requirements gathering and user stories within these methodologies to help different parts of organizations work together effectively.