Abstract
We are built to search. Our ancestors foraged for food. We search for pens, keys, and cars in parking lots. Even when the stimulus is visible, we must search because we cannot fully process all visual stimuli at once. I will discuss the limits on vision without attention and some of the mechanisms of visual search. I will then turn to real-world tasks like the search for cancer in X-rays or security threats in luggage. I will show how our normal processes of search can lead to serious problems in socially important tasks.