O'Reilly Automotive is one of the largest U.S. specialty retailers of automotive aftermarket parts, tools, supplies, and accessories — products like brake parts, batteries, alternators, filters, oil, and wiper blades. O'Reilly's core strategy is its "dual market" model, serving both DIY customers (individuals repairing their own vehicles) and professional customers (auto repair shops, mechanics, and fleet operators) from the same store network, with each segment representing roughly half of sales. O'Reilly operates 6,585 stores across the U.S., Puerto Rico, Mexico, and Canada. Revenue grows through two levers: comparable store sales growth and new store openings. O'Reilly's distribution network is tiered: 32 distribution centers stocking 156,000+ SKUs feed 399 larger hub stores, which in turn provide same-day delivery to smaller regular stores — allowing broad parts availability without requiring every store to carry deep inventory. Over 95% of stores receive multiple same-day deliveries, which is critical to serving professional customers who need parts immediately. Private label products represent over 50% of sales, providing supplier negotiating leverage and higher gross margins. Growth priorities include U.S. store densification, expansion into underpenetrated markets like the Mid-Atlantic and Northeast (enabled by a new Virginia distribution center), accelerating company-operated stores in Mexico, and early-stage expansion into Canada. O'Reilly returns capital entirely through share buybacks, having repurchased $27B in shares since 2011.