Efforts to increase female representation in leadership positions have seen limited success. Studies indicate that beyond structural barriers, a gender gap exists in the willingness to lead. We suggest responsibility aversion as a factor in women's lower willingness to lead and propose co-leadership as a solution. Our research, involving three experiments with 2,700 participants and data from 6,774 US companies, shows women are more willing to lead in co-leadership roles due to shared responsibility reducing psychological costs. Additionally, co-leadership attracts leaders with lower competitiveness and dark personality traits, offering a potential solution to promote diversity in leadership.