Public debates about the gender pay gap tend to become polarized quickly. On one side, the gap is often presented primarily as evidence of persistent discrimination. On the other, it is explained mainly by differences in career choices or hours worked. The empirical reality is more complex. In an integrative review published in the Journal of Organizational Behavior, Beth A. Livingston, Sujin Jeong, Felice B. Klein, and Anushka Chakroborty examine several decades of research from economics, sociology, and organizational psychology to better understand the causes of the phenomenon. Their objective is straightforward: organize a large but fragmented body of literature to better explain why women still earn less than men in most countries.
The authors show that the explanations proposed in the research literature can largely be grouped into four families. The first concerns human capital accumulation. Career trajectories often differ, particularly because of career interruptions, differences in hours worked, or specialization in certain types of roles. Over time, these factors can slow salary progression. The second family involves bias and discrimination. Even when qualifications and positions are comparable, some studies show that salary evaluations, promotions, or negotiations can favour men. The third family relates to occupational sorting. Women and men are not distributed in the same way across sectors, occupations, and organizations, and some contexts offer more favourable compensation structures than others. For example, women are more represented in care-related and community fields, while men are more common in information technology or the finance industry. Finally, a fourth family includes differences linked to socialization and preferences, such as approaches to salary negotiation, tolerance for long working hours, or attraction to certain types of roles.
These mechanisms also help explain how the gap evolves over time. Much of the progress observed over the past decades is linked to the convergence of human capital. In many countries, women are now as educated as men, if not more so. But as these differences narrow, other mechanisms become more visible. Career interruptions related to parenthood, occupational segregation, or compensation systems that strongly reward long working hours can continue to sustain part of the gap. In some cases, these factors reinforce one another. For instance, a sector that strongly values evening availability or international mobility may indirectly favour certain career trajectories over others.
The complexity of this research contrasts with the simplicity of the arguments that sometimes appear in public debates. Most people agree that reducing pay differences between women and men is an important goal. Unfortunately, there are unlikely to be one or two simple solutions that will make the problem disappear. And yet, this is not a reason to stop working to improve the situation.