Behavior analysis emerged from the nonhuman laboratories of B. F. Skinner, Fred Keller, Nate Schoenfeld, Murray Sidman, James Dinsmoor, Richard Herrnstein, Nate Azrin, and others who pioneered experimental preparations designed to do one thing - find orderly relations between environment and behavior. This bottom-up approach to a natural science of behavior yielded a set of behavioral principles that proved orderly and replicable across subjects, laboratories, and species. By the 1960s, behavior analysts began translating these principles into interventions for institutionalized humans characterized by impoverished repertoires of adaptive behavior. When these interventions proved successful in replacing problem- with adaptive-behavior, the field of Applied Behavior Analysis was born. Over the last 50 years the field of behavior analysis has grown substantially both in the number of practicing behavior analysts and the range of behavior to which behavioral principles have been applied. Today the laboratory study of basic principles of behavior continues to expand our understanding of behavior and to inform the treatment of disorders ranging from autism to substance abuse. The present volumes continue this inductive translational approach to the science of behavior analysis by providing overview and in-depth chapters spanning the breadth of behavior analysis.