Walgreens Health Initiatives (WHI) was the pharmacy benefit management arm of drugstore giant Walgreen, and while it is no longer part of the drug retail chain, it still administers the pharmacy benefit programs for millions of members in the US. Its services include formulary design, disease management programs, and mail-order pharmacy services that help companies lower their health insurance costs. WHI also manages the complex drug regimens for patients with serious diseases such as cancer and HIV. The company was acquired by Catalyst Health Solutions for $525 million in 2011.