This chapter outlines behavioral measures related to the control of attention and functional theories of attention based on such measures. It focuses on the control of visual attention in both normal and neurologically impaired individuals. The major types of attention are: spatial attention, in which stimuli are selected based on their position in space; object-based attention, in which stimuli are selected based on their identity; attentional selection in visual working memory, in which attention selects items that will be remembered; and executive attention, in which attention is involved in choosing which task or behavior an observer will perform. The chapter provides evidence for a number of cerebral sites that appear to be involved in the overall control of attention. Understanding how these sites interact and how they relate to functional theories of attentional control increases understanding of normal and disordered attentional control processes.