The estimation of genetic models reported by J. L. Jinks and L. J. Eaves in a recent review are critically examined. A number of errors in procedure and interpretation are found. It is concluded that the evidence, provided by kinship correlations, for the proposition that intelligence is highly heritable, is not persuasive. (Author/BJG)

Ronald C. Johnson argued that if early environmental stimulation or deprivation has a significant effect on intellectual ability, then individuals who are genetically identical and who are exposed to a common early environment should resemble one another more closely in IQ than similar individuals who have not shared a common environment. Johnson…

This special issue of the "Courrier," a journal for professionals concerned with issues related to the physical and psychological development of children, provides (1) an overview of 25 years of internationally coordinated research, (2) a selection of papers published by the research teams, and (3) a description of the teams and their…