Sure, formularies limit choice. Doctors, nurses, many patients—not fans. The rhyme and reason? Calculations of cost and effectiveness. This issue of Managed Care looks at what formularies have become—and the crescendo of calls for reform. Rebates are driving decisions about which drugs make the lists. Employers are frustrated by the secrecy of those rebates deals—but also hesitant to rock the boat; rebates help knock down their soaring health care costs. Meanwhile, spread pricing and specialty drugs, which don’t lend themselves to formulary tactics, are roiling the waters. Read this issue to navigate the white water.