I conducted research at the Rockefeller Archive Center for my dissertation and current book project on the history of psychological testing in American business. My work has examined the network of psychologists and management experts who developed and implemented personality tests, such as the popular Myers-Briggs Type Indicator. The Rockefeller Archive Center was a crucial site to understand the origins, spread, and influence of personality tests. As a historian of science and business, I sought to understand the translations and circulations of research between psychologists and business. I focused particularly on the way that research into personality and work refracted existing social inequalities and biases of race and gender, at the same time that researchers sought to counter inequality through psychological testing. Both the Rockefeller and Ford Foundations funded research in personality psychology and in management that studied the psychological capacities associated with creative and managerial work. In particular, these two foundations both provided direct grants to four key organizations discussed in this report: Berkeley's Institute for Personality Assessment and Research (IPAR), Educational Testing Service (ETS), the Opportunities Industrialization Commission (OIC), and the Public Agenda Foundation (PAF). IPAR and ETS were especially important as early sites for research and publications on the Myers-Briggs Type Indicator, a personality test whose history I examine in my project. OIC and PAF both conducted research and implemented training programs that linked motivational psychology to the work ethic. All four organizations were important sites for studying the personality traits associated with work in 20th-century America.