Some of the procedures for developing and validating learning sequences or learning hierarchies are explored. For each of these procedures, references are provided that can be used for additional study or clarification of the procedures. (Author)

A theory of practice in high-proficiency skills such as speech production is proposed, involving activation of a hierarchy of nodes in serial order within an output system of behavior. Increased flexibility with practice, response mechanism transfer in skills, motor equivalence, automaticity, and speed-accuracy trade-off are discussed. (Author/CM)