What worker competencies are most important for the 21st century? And can it be shown that to possess them makes a difference in educational or economic outcomes for individuals and organizations? This report summarizes key insights and empirical findings from a wide range of literature on these questions. The report’s sponsor, the Hewlett Foundation, asked us to focus on 15 general competency areas. These are reviewed under 5 broad categories: analytic skills, interpersonal skills, ability to execute, information processing, and capacity for change/learning.