The Mother-Child Home Program was designed to modify the early cognitive experience of preschool disadvantaged children by "intervening" with a series of verbal stimulation activities planned to raise the child's measured IQ. Intervention was timed to occur with early speech development and within the context of family relationships. The program provided for structured verbal interaction between 2- and 3-year-old children and their mothers, centered around toys and books brought as gifts to the child by a trained program staff member. The program had four major components: 1) a focus on mother-child pairs; 2) the use of trained toy demonstrators who worked with the mother and child in their home; 3) Verbal Interaction Stimulus Materials (VISM) consisting of toys and books which formed the basis of the relationship; and 4) supervision, including selection of VISM according to specific criteria, development of methods to insure proper presentation of VISM, and monitoring the work of the toy demonstrators with each pair. Children in the treatment group showed statistically and educationally significant IQ gains when both professional social workers and trained nonprofessionals were used as toy demonstrators. (LH)