The relationship between Piagetian theory and its application in three early childhood programs is discussed in two papers with differing points of view. The first paper discusses Piaget's epistemology and presents a critical analysis of the three programs, concluding that only one of them is consistent with Piaget's epistemology. A rejoinder, challenging the first paper's analysis, suggests an alternative approach to examining the relevance of Piaget to early childhood education. The programs under discussions are: (1) Weikart's Cognitively Oriented Curriculum, (2) Lavatelli's Early Childhood Curriculum: A Piaget Approach, and (3) Kamii and DeVries' Piaget for Early Education. The programs are examined in the first paper in relation to (1) nature of subject-object relationship, (2) construction of operations, (3) nature of physical and logico-mathematical knowledge, and (4) representation of knowledge. Conclusions emphasize the conflict between constructionalist epistemology and empiricist tradition. The second paper questions whether sophisticated knowledge of Piaget's epistemological theory is necessary for teachers and criticizes the distinction made in the first paper between psychological and epistemological perspectives. Recognition of what Flavell calls Piaget's stage-independent and stage-dependent theories is urged, with emphasis on the latter to provide a specific framework for teachers and parents. Questions to be addressed by teachers and researchers in early childhood education are proposed. (BF)