Lloyd Shapley, game theorist and co-recipient of the 2012 Nobel Memorial Prize in Economic Sciences, passed away in March. This column, by the economist with whom he shared the Nobel, outlines Shapley’s intellectual life and career, which was among the most fertile of the 20th century. Shapley made fundamental contributions to the analysis of both cooperative and non-cooperative games. Some of his foundational ideas have led to the study of matching markets and to the thriving branch of practical economics known as ‘market design’.