Investigation of the basic mechanisms of chronic pain not only provides insights into how the brain processes and modulates sensory information but also provides the basis for designing novel treatments for currently intractable clinical conditions. Human brain imaging studies have revealed new roles of cortical neuronal networks in chronic pain, including its unpleasant quality, and mouse studies have provided molecular and synaptic mechanisms underlying relevant cortical plasticity. This review paper will critically examine the current literature and propose a cortical network model for chronic pain.