Grounded in social cognitive and self-determination theory, one purpose of the large-scale investigation reported in this volume was to determine whether elementary-aged children (7-12 years old) are progressing toward attainment of the psychomotor assessments that have been recommended for predicting achievement of National Association for Sport and Physical Education (NASPE) Standards 1 (motor competence), 3 (regular participation in activity), and 4 (health-enhancing level of fitness). Other primary purposes were (1) to understand the relationship between and among motor competence, regular participation in physical activity, and fitness; (2) to compare students' personal attributes, experiences in, perceptions of, and motives for participation in physical activity; and (3) to understand the association of environmental access to motor competence, physical activity, and fitness. This article provides a general description of the research program represented by the other studies in this volume. (Contains 2 tables.)