We analyzed data from the Australian Study of Health and Relationships, a national telephone survey (2001-2002) of sexual behavior and attitudes among a representative sample of 19,307 Australians aged 16 to 59. Respondents were asked whether at their last sexual encounter they gave or received manual stimulation and oral sex, had vaginal intercourse or anal intercourse, and whether they had an orgasm. Most encounters (95%) included vaginal intercourse. Of the 64 possible combinations of practices, 13 accounted for 93% of encounters: vaginal intercourse alone (12%), intercourse and manual stimulation of the man's and/or woman's genitals (49%), and intercourse, manual, and oral (32%). Men had an orgasm in 95% of encounters and women in 69%. Women were more likely to reach orgasm in encounters including more practices, especially cunnilingus. Demographic and sexual history variables were comparatively weakly associated with orgasm.