(1) Skeletal motility is a significant form of pleasure seeking and of reality testing and of integration throughout life, with characteristic ontogenesis and psychological corollaries. (2) The second year of life is dominated by motor pleasure and mastery and might be considered the motor phase of ego and libido development. (3) The vicissitudes of the development of the global aspects of motility and its psychological concomitants contribute both to normal development and to psychogenic motor disturbances and to other forms of neuroses and psychoses. (4) The utilization of motor data contributes to and may be indispensable in the treatment of children and adults.