In recent years, the retirement age for public pensions has increased across many countries, and additional increases are in progress or under discussion in many more. The seventh stage of an ongoing research project studying the relationship between social security programs and labor force participation, Social Security Programs and Retirement around the World: The Capacity to Work at Older Ages explores people's capacity to work beyond the current retirement age. It brings together an international team of scholars from twelve countries--Belgium, Canada, Denmark, France, Germany, Italy, Japan, the Netherlands, Spain, Sweden, the United Kingdom, and the United States--to analyze this issue. Contributors find that many--but not all--individuals have substantial capacity to work at older ages. However, they also consider how policymakers might divide gains in life expectancy between years of work and retirement, as well as the main impediments to longer work life. They consider factors that influence the demand for older workers, as well as the evolution of health and disability status, which may affect labor supply from the older population.