This chapter uses the Health and Retirement Study to describe the relationship between work and health for older persons by age. We examine not only the patterns within a given cross-section, but also we study trends in health at ages 51-56 between 1992 and 2004. Most retirement occurs well before the onset of work-limiting disability, leaving a large reserve of potential for longer worklives. Baby Boomers will likely have to draw on this reserve, yet its health is not demonstrably better than that of persons born a dozen years earlier. Nevertheless, advances in medical care for health conditions that most 51-56 year olds have not yet encountered may still yield better health at older ages for the Boomer cohort.