We examined whether similarity, complementarity, accuracy, and positive illusions exist within the sex lives of same-sex romantic couples. Partners had similar and complementary sexual desires and they perceived each other's desires with considerable accuracy; these effects were greater than in randomly matched pseudocouples. As evidence of positive sexual illusions, people overperceived sexual similarity and complementarity, and they overperceived the accuracy with which their partner knew their desires. Using actor–partner interdependence models (D. A. Kenny, D. A. Kashy, & W. L. Cook, 2006), similarity, complementarity, and positive illusions predicted sexual satisfaction, but a partner's actual accuracy did not. In parallel with earlier findings from heterosexual couples, this work indicates that positive sexual illusions are motivated cognitive processes that benefit sexual satisfaction, as theories of relationship maintenance suggest.