More children and working-age Americans are going without prescription drugs because of cost concerns, according to a new national study by the Center for Studying Health System Change (HSC). In 2007, one in seven Americans under age 65 reported not filling a prescription in the previous year because they couldn’t afford the medication, up from one in 10 in 2003. Rising prescription drug costs and less generous drug coverage likely contributed to the growth in nonelderly Americans—from 10.3 percent in 2003 to 13.9 percent in 2007—who went without a prescribed medication. The most vulnerable people—those with low incomes, chronic conditions and the uninsured—continue to face the greatest unmet prescription drug needs. Uninsured, working-age Americans saw the biggest jump in unmet prescription drug needs between 2003 and 2007, with the proportion rising from 26 percent to almost 35 percent. At the same time, a growing proportion of working-age Americans with employer-sponsored insurance reported going without prescription medications. The number of Americans who cannot afford prescription medications is likely to grow as the economy continues to decline and the ranks of the uninsured grow.