The Global Study of Sexual Attitudes and Behaviors (GSSAB) is an international survey of various aspects of sex and relationships among adults aged 40-80 y. An analysis of GSSAB data was performed to estimate the prevalence and correlates of sexual problems in 13,882 women and 13,618 men from 29 countries. The overall response rate was modest; however, the estimates of prevalence of sexual problems are comparable with published values. Several factors consistently elevated the likelihood of sexual problems. Age was an important correlate of lubrication difficulties among women and of several sexual problems, including a lack of interest in sex, the inability to reach orgasm, and erectile difficulties among men. We conclude that sexual difficulties are relatively common among mature adults throughout the world. Sexual problems tend to be more associated with physical health and aging among men than women.