Basic cognitive mechanisms, such as the abilities to briefly maintain, focus, and process information decline gradually as people get older. These phenomena have attracted much public and research attention. Many subfields of cognitive aging research have been advancing rapidly, but mostly in an independent disintegrated fashion until the late 1990s. The first decade of the twenty-first century has seen much more integrated research efforts that help advanced out understandings about the links between the aging mind and aging brain. This article reviews various aspects of aging cognition occurring at the behavioral, information processing, and neurobiological levels, and describes general theoretical considerations aimed at integrative research across different fields.