In a pilot study of children's drawings of "a house with a tree behind it," Piagetian sequence (scribbling, fortuitous realism, failed realism, intellectual realism, and visual realism) was tentatively supported. Children's strategies in decentering from intellectual to visual realism were noted. The study reported in this paper was undertaken to investigate: (1) the developmental sequence in House-Tree task; (2) its relationship with Stanford Binet, Peabody, and four Piagetian measures; and (3) synchronous development among these measures. Data from 49 subjects aged, 3 1/2-6 1/2 years, were used for analysis. Developmental sequence for House-Tree task and relationship among these measures was confirmed. Some evidence for synchronous development at a younger age level was found. The House-Tree task, because of its simplicity, ease, and economy in administering and scoring, has potential for assessing the cognitive development of young children. (Author/ED)