Effective collaborative problem solving comprises cognitive dimensions, in which men tend to outperform women, and social dimensions in which women tend to outperform men. We extend research on between-country differences in gender gaps by considering collaborative problem solving and its association with two indicators of societal-level gender inequality. The first indicator reflects women's underrepresentation in the labor market and politics. The second reflects women's underrepresentation in stereotypically masculine fields and men's underrepresentation in stereotypically feminine fields among university students. We use cross-country evidence on collaborative problem-solving skills among 15-year-old students from 44 countries (N = 343,326) who participated in the 2015 Programme for International Student Assessment (PISA). Girls outperform boys in collaborative problem solving in all countries. Gender gaps in collaborative problem solving in favor of girls are less pronounced in countries where women are especially underrepresented in the labor market and politics but more pronounced in countries where men and women are more likely to conform to gender stereotypes in selecting a field of study at university. Societal-level gender equality plays a bigger role in explaining between-country differences in achievement in domains with a gender gap in favor of girls—such as collaborative problem solving and, to a lesser extent, reading—and a smaller role in explaining between-country differences in achievement in domains with a gender gap in favor of boys—such as mathematics.