Thomas M. Achenbach  Thomas M. Achenbach (born 1940) is Professor of Psychiatry and Psychology and President of the nonprofit Research Center for Children, Youth, and Families at the University of Vermont. With many collaborators, he has conducted extensive research on evidence-based assessment of and strengths for ages 1½ to over 90 years. This research has yielded empirically derived syndromes of psychopathology, plus broad patterns of problems for which he coined the now widely used terms “Internalizing” and “Externalizing. As an outgrowth of his research on relations between development and psychopathology, he authored a 1974 book entitled “Developmental Psychopathology, which laid the foundations for the discipline of that name. Achenbach has authored more than 300 publications, including over 30 books, monographs, and assessment manuals. He has given some 400 invited presentations in 45 countries. Achenbach was born in Stamford, Connecticut, and grew up in Wethersfield, Connecticut. He earned his bachelor's degree Summa Cum Laude from Yale University and spent a postgraduate year at the University of Heidelberg as a German Government Fellow. He earned his Ph.D. at the University of Minnesota, followed by an NIMH Postdoctoral Fellowship at the Yale Child Study Center. Achenbach served as Assistant Professor and then Associate Professor in the Department of Psychology and the Child Study Center at Yale from 1967 through 1975. In 1971-72, he was a Social Science Research Council Senior Faculty Fellow at Jean Piaget’s Centre d’Epistémologie Génétique in Geneva, Switzerland. From 1975 through 1980, he was a Research Psychologist in the Laboratory of Developmental Psychology at the National Institute of Mental Health, where he served on the Research Advisory Group to the Director of the Institute. Since 1980, he has been Professor of Psychiatry and Psychology at the University of Vermont, where he was Director of Child and Adolescent Psychiatry from 1984 through 2007. He has been Chair of the American Psychological Association’s Task Force on Classification of Children’s Behavior and a member of the American Psychiatric Association’s Task Force on DSM-III-R. In 2000, he founded the nonprofit Research Center for Children, Youth, and Families at the University of Vermont and has served as President of the Center since it was founded. Achenbach and his colleagues have developed a family of standardized instruments for assessing people’s behavioral, emotional, social, and thought problems, competencies, adaptive functioning, and strengths.