RELATED: If You and Your Partner Can’t Agree on This, It’s Time to Break Up. To conduct their study, researchers from Martin Luther University Halle-Wittenberg (MLU) and the University of Bamberg spoke with 181 straight couples who had been together for an average of eight years and were living together for at least one month. The participants, whose ages ranged from 18 to 71, responded to survey questions about a variety of aspects of their relationship, including trust, sexual satisfaction, feelings of oppression and constraint, and commitment and willingness to invest in the relationship. The researchers were looking to find out how actual and perceived power influenced each of these aspects of their relationship. “We also calculated the balance of power to investigate the extent to which the traits of each partner were similar to each other,” one of the study’s authors Robert Körner, PhD, of the Institute of Psychology at MLU, said in a statement. The researchers found that the “happiest couples were those in which both partners reported a high sense of personal power,” according to the researchers’ statement. For the purpose of the study, which was published in the Journal of Social and Personal Relationships on June 28, “power is about being able to influence people and successfully resist the attempts of others to influence you.” When it comes to your partner, this means feeling like you have the opportunity to decide on issues that are important to you within your relationship. RELATED: Your Relationship Is Doomed If Your Partner Does This, Experts Say. According to the study, the most essential factor of satisfaction within a relationship when it comes to power is not the balance of power but rather the personal level of power each person believes they have. While this may seem contradictory to what makes a strong relationship, one of the co-authors of the study, Astrid Schütz, PhD, explained that it doesn’t have to be.ae0fcc31ae342fd3a1346ebb1f342fcb “Maybe this feeling extends to different aspects of the relationship. Whereas the woman might want to decide on where to go on vacation, the husband chooses where to go for dinner,” Schütz, a researcher from the University of Bamberg, said in the statement. To maintain a happy relationship, both people need to have the opportunity to make decisions about their shared life that are important to them; otherwise, they won’t be satisfied. “The feeling of being able to make decisions in a marriage… has a big influence on the quality of the relationship,” Körner said. He added that the subjective feeling of having power and the ability to act freely notably positively impacted the quality of the relationship. Earlier studies showed that power was rarely balanced in relationships in the past, with men frequently having more influence on decisions than women. As society has moved away from traditional gender roles, the power dynamics have shifted with them, the researchers note. “Romantic relationships have become more equal—especially in western societies,” Körner said. RELATED: For more up-to-date information, sign up for our daily newsletter. While gender roles have certainly shifted over time, the researchers found that men still had more positional power in a traditional sense, like having a higher income and more education. Additionally, the need to make decisions tended to be stronger in men. “With respect to positional power, an imbalance was observed,” the authors wrote. “Men reported having significantly more positional power, operationalized as educational and occupational qualification as well as higher income, than women.” In regards to the latter, they added, “Women still have less positional power than men, there is still a gender pay gap, and men work in better paid jobs.” However, researchers said these factors surprisingly didn’t influence the quality of the relationship. In fact, “many women were more satisfied with the relationship when the partner felt that he is in charge, which is in line with traditional gender roles,” the authors wrote. Most of the happy couples in the study said they felt like both they and their partner were able to assert their preferences about the things that mattered most to them. RELATED: If Your Partner Is Using These 2 Words, You May Be Headed for a Breakup.