We studied several traits in a novel, insightful, and efficient experimental design, examining 2,400 male–female pairs in a “round-robin” array, where each female was tested against multiple males and vice versa. To remedy this imbalance, we analyze a textbook example of sexual selection in the stalk-eyed fly ( Diasemopsis meigenii). They ignore a range of less obvious traits and behavior, in both sexes, involved in the interactions leading to mate choice. All too often, studies of sexual selection focus exclusively on the responses in one sex, on single traits, typically those that are exaggerated and strongly sexually dimorphic.