There is a longstanding belief in relationship science and popular opinion that women are the barometers in mixed-gender relationships such that their perceptions about the partnership carry more weight than men's in predicting future relationship satisfaction, but this idea has yet to be rigorously tested. We analyze data from two studies to test within-person links between men's and women's relationship satisfaction on their own and their partner's next-day and next-year satisfaction. Study 1 combined nine daily diary datasets from Canada and the United States with 901 mixed-gender couples who provided 29,541 daily reports of relationship satisfaction. Study 2 analyzed five annual waves of data from the German Family Panel (pairfam) that surveyed 3,405 mixed-gender couples who provided 21,115 relationship satisfaction reports. Latent curve models with structured residuals (LCM-SR) revealed that in both studies, men's and women's relationship satisfaction significantly predicted their own and their partner's relationship satisfaction, with no gender differences in the magnitude of these effects. Results underscore the interdependence of romantic partners' satisfaction and indicate that both men and women jointly shape romantic relationship satisfaction.