Background: The Global Study of Sexual Attitudes and Behaviours was a survey of 27 500 men and women in 29 countries. Here we report the sexual activity, the prevalence of sexual difficulties and related help-seeking behaviour among participants in Australia. Methods: A telephone survey was conducted in Australia in 2001–2002, with interviews based on a standardised questionnaire. A total of 1500 individuals (750 men and 750 women) aged 40 to 80 years completed the survey. The questionnaire covered demographic information, overall health, and sexual behaviours, attitudes and beliefs. Results: Overall, 83% of men and 74% of women had engaged in sexual intercourse during the 12 months preceding the interview, and 38% of all men and 29% of all women engaged in sexual intercourse more than once a week. Early ejaculation (23%), erectile difficulties (21%) and a lack of sexual interest (18%) were the most common male sexual difficulties. The most frequently reported female sexual difficulties were: lack of sexual interest (33%), lubrication difficulties (26%) and an inability to reach orgasm (25%). Older age was a significant predictor of male erectile difficulties and of lubrication difficulties in women. Only a minority of men and women had sought help for their sexual difficulty(ies) from a health professional. Conclusions: Many middle-aged and older adults in Australia report continued sexual interest and sexual activity. Several sexual difficulties are highly prevalent in this population, but those experiencing these difficulties rarely seek medical help. This may be because they do not perceive such difficulties as serious or sufficiently upsetting.