How does experience change the way we perceive the world? This Element explores the interaction between perception and experience by studying perceptual experts, people who specialize in recognizing objects such as birds, automobiles, dogs. It proposes perceptual expertise promotes a downward shift in object recognition where experts recognize objects in their domain of expertise at a more specific level than novices. To support this claim, it examines the recognition abilities and brain mechanisms of real-world experts. It discusses the acquisition of expertise by tracing the cognitive and neural changes that occur as a novice becomes an expert through training and experience. Next, it looks under the hood of expertise and examines the perceptual features that experts bring to bear to facilitate their fast, accurate, and specific recognition. The final section considers the future of human expertise as deep learning models and artificial intelligence compete with human experts in medical diagnosis.