Musical improvisation refers to spontaneous generation of novel musical compositions in the moment of performance. The neural correlates of musical improvisation have been studied using functional brain imaging studies (fMRI, PET) as well as electrophysiologic techniques (EEG, tDCS). These studies reveal a broad network of brain regions recruited during musical improvisation. These regions participate in domain-general processes such as attention and executive control; rule-based motor sequence generation, selection, timing, and execution; sensorimotor integration; multimodal sensation; emotional processing; and interpersonal communication. Improvisational expertise appears to modulate how attentional networks are recruited during improvisation, and also enhances functional connections between motivational, sensory, limbic, and motor regions. Understanding the neural correlates of musical improvisation provides broader insights into the cognitive basis of creativity.