This chapter focuses on select contributions of cognitive psychology to understanding psychiatric disorders and treatment. We begin with a brief history of the origins of modern cognitive psychology and then discuss the rationale for viewing cognition as a set of modular, yet connected, functional information-processing steps rooted in specific structures of the brain. The core cognitive processes we discuss include attention, memory, executive function, and social cognition. For each process, we outline its neural underpinnings and implications for the cognitive, emotional, and social deficits that characterize particular psychiatric disorders.