Segment strategy is the practice of grouping customers based on common characteristics, needs, or behaviors, then building tailored strategies (messaging, pricing, features, sales approach) for each group. It's the bridge between understanding your market and making product/marketing decisions. You analyze data to identify meaningful customer segments, develop personas to represent each, and design GTM plays that resonate with each group. Segmentation is fundamental to product-market fit. A one-size-fits-all approach doesn't work; different customers have different needs. Segmentation lets you be precise and effective.