Gender inequality is a major part of the global jobs challenge. Appropriate responses require leveling the playing field and creating the types of jobs that can empower women. Gender inequality in the world of work has been stubbornly persistent across multiple dimensions, despite relatively large gains in recent decades in women's health and education. This report focuses on one dimension of inequality that is often related to other aspects of disadvantage. The starting point is the recognition that women are disadvantaged globally on virtually every indicator in the world of work - earnings, quality of employment, employment status, participation, and that these differences matter for development. This report was initiated as a companion to the world development report (WDR) 2013 on jobs and builds on key findings and frameworks from both the report and the preceding WDR 2012 on gender equality and development. The value added of this report is to revisit the key constraints to gender equality in the world of work in light of new evidence, and go more deeply into the importance of women's agency for boosting their participation in the world of work (and vice versa) using a lifecycle perspective. Global action is needed to fill knowledge gaps about the problems of, and the solutions to, gender inequality in the world of work. The World Bank recently launched enGender impact, a gateway to its gender-related impact evaluations. This effort complements gender innovation and evaluation initiatives in Sub-Saharan Africa and Latin America and the Caribbean, and efforts by the International Finance Corporation (IFC) to highlight good business practices.