and their environments, and the histories of the cultural practices through which they lead their lives. Taken together, these domains of social science theory and methodology have informed the diverse research projects of the members of the LCHC. By integrating these approaches, LCHC researchers combine cultural-historical psychologists’ insistence on historical/developmental analysis (influenced by Marxism) with anthropologist's/pragmatist's emphasis on the analysis of concrete activity systems and the diversity of such systems within and between societies. Origins and history The LCHC emerged during the Civil Rights Movement, a time when issues regarding education and employment for minorities were being sharply debated. On a world scale, groups such as UNESCO were concerned with how to improve education throughout the developing world. This historical context motivated foundations to give grants to LCHC to conduct research on apparent cultural variations in cognitive development and their significance for maximizing success in schooling. LCHC was originally based at Rockefeller University in New York City from 1971 to 1978 and has been based at the UC San Diego (UCSD) from 1978 to the present. When the LCHC relocated from New York to California, it changed both its university and departmental setting, with its new base of operations now in the Department of Communication. This institutional relocation permitted the LCHC to: 1) expand its research concerns to include the use of new communication technologies in various settings; 2) forge community partnerships in the racially, economically, and politically diverse border-city of San Diego; and 3) situate LCHC research within the discipline of communication studies, for which mediation is a central, constitutive, concept. Cross-cultural studies The LCHC has participated in key cross-cultural studies, such as research projects with the Kpelle people and the Vai people (both of Liberia), and rural residents in Yucatan, Mexico. These studies were instrumental in formulating a critique of contemporaneous methods of cross-cultural and developmental psychology. LCHC researchers argued that studies of human cognitive activity must be grounded in the actual materials and processes of people's daily lives (ecological validity). Using this approach, they demonstrated that years of schooling strongly influence performance on many common cognitive tasks, but that such influences do not support the conclusion of a general cognitive impact of schooling on cognitive development. This work called into question the use of cognitive tasks to measure school achievement by showing that schooled children scored better on psychological tests while performing far below expectations on their