Cencora is one of the largest pharmaceutical distributors in the U.S., buying drugs from manufacturers and distributing them to healthcare providers — primarily pharmacies, hospitals, and specialty physician practices. Cencora distributes brand-name, specialty, and generic pharmaceuticals, along with over-the-counter products and home healthcare supplies. The core business is a middleman model: Cencora earns a margin on each product it distributes, with economics varying by drug type. Specialty drugs — used to treat complex conditions like cancer and eye disease — are the highest-margin and fastest-growing part of the business. Cencora has a leading position in specialty distribution, particularly to community oncologists and retina specialists. The U.S. Healthcare Solutions segment represents roughly 94% of revenue; the remaining 6% comes from International Healthcare Solutions, which includes Alliance Healthcare (European wholesale distribution), World Courier (specialty clinical trial logistics), and Innomar (Canada). Walgreens accounts for roughly 25% of revenue, and Evernorth (Cigna's pharmacy benefit business) accounts for roughly 13%. Cencora is expanding beyond pure distribution through investments in managed service organizations (MSOs) — specifically Retina Consultants of America and a 35% stake in OneOncology — providing back-office services like revenue cycle management and analytics to physician practices. Cencora is also investing $1B through 2030 in U.S. distribution infrastructure to handle growing specialty drug volume.