Dale T. Mortensen was an American economist known for his significant contributions to labor economics and search theory. Born on February 2, 1939, he was awarded the Nobel Prize in Economic Sciences in 2010, alongside Peter A. Diamond and Christopher A. Sims, for their analysis of markets with search frictions. His work helped explain how unemployment and job vacancies coexist in the economy. Mortensen served as a professor at Northwestern University and was influential in shaping economic policies related to labor markets. His research provided insights into the dynamics of job creation and destruction, enhancing the understanding of how individuals and firms interact in the job market.